The BIG Technical Jargon Guide

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A Glossary of Computer Technical Terms Explained

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This page offers a comprehensive look at common computing terminology. Explore more technical terms by choosing a different topic from our menu or enter a specific query into the search box to get started. Please note that our BIG terminology guide has hundreds of entries so if you use a common word in your search, you may have to scroll through several results to find what you're looking for.

Last modified: February 2024

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What is an (I/O) Device?

(I/O) stands for input-output, and the terminology is pronounced '(Eye | Oh) device'. There are many IO devices that connect to a computer, like: a display monitor, printer, mouse, keyboard or external hard drive. A device does not need to communicate both ways for it to be classed as an IO device, although some items do communicate both ways. For example, a keyboard is the most common input device on a computer, and a computer monitor screen is used for the output.

What is an algorithm?

An algorithm is a set of instructions or rules that a computer follows to perform a specific task or solve a problem. It's like a recipe that tells the computer what steps to take to complete a task.

For example, a sorting algorithm is a set of instructions that tells the computer how to arrange a list of items in a particular order, such as from smallest to largest. Another example is a search algorithm, which tells the computer how to look for a particular piece of information in a large database or document.

Algorithms can be very simple or very complex, depending on the task they are designed to perform. They are an essential part of computer programming and are used to automate tasks, analyse data, and make decisions based on predefined rules or criteria.

What is APFS file format?

APFS is a file format used by Apple MAC computers. It has been optimised for flash and SSD storage. MacOS 10.13 or later supports the APFS file format for both bootable and data volumes.

The following additional file formats can also be used for MAC computers using macOS 10.13 or later:

APFS - Uses the APFS format. Choose this option if you don’t need an encrypted or case-sensitive format.

APFS (Encrypted) - Uses the APFS format and encrypts the volume.

APFS (Case-sensitive) - Uses the APFS format and is case-sensitive to file and folder names. For example, folders named 'Accounts' and 'ACCOUNTS' are two different folders.

APFS (Case-sensitive, Encrypted) - Uses the APFS format, is case-sensitive to file and folder names and encrypts the volume. For example, folders named 'Accounts' and 'ACCOUNTS' are two different folders.

See OS Extended (Journaled) for Apple computers operating macOS 10.12 or earlier.

What is Bluetooth?

Bluetooth is a wireless communication technology that allows devices to connect and exchange data over short distances. It works by using radio waves to establish a secure and low-power connection between two or more Bluetooth-enabled devices, such as smartphones, laptops, headphones, or speakers. Bluetooth technology is widely used for wireless audio streaming, file transfer (AirDrop), and device control. For example, you can use Bluetooth to connect your smartphone to a wireless speaker and play music, or connect your mobile phone to a hands-free car kit. Bluetooth is a convenient and versatile technology that eliminates the need for wires or cables, and it has become a standard feature in many modern devices.

What is a computer bug?

A computer bug is like a mistake or glitch in a computer program that causes it to act in ways it's not supposed to. It's kind of like a typo in a document that might cause confusion or misunderstanding. The bug might make the program crash, freeze, or produce incorrect results, and it can happen for a variety of reasons. Sometimes it's because the program was written with errors, or there might be a problem with the computer's hardware or software. To fix the bug, programmers need to identify and correct the problem, which can take some time and effort.

What is a CD-ROM?

A CD-ROM (Compact Disc-Read Only Memory) is a type of optical disc that stores digital data. It looks like a regular audio CD, but instead of containing music, it holds software, applications, or other types of data. A CD-ROM can store up to 700 megabytes of data. CD-ROMs were commonly used in the past for software installation, game playing and storing large data files. While they have been largely replaced by other storage media, such as USB drives and cloud storage, they are still used in some industries and applications today.

What is cloud storage?

Cloud storage is like having a virtual locker where you can store your digital files and access them from anywhere with an internet connection. Instead of keeping your files on your computer or other physical devices, you store them on servers owned and maintained by cloud storage providers, such as Google Drive, Dropbox, or iCloud. This means you don't have to worry about losing your files if your computer crashes or gets stolen and you can easily share your files with others. Cloud storage is convenient and flexible, but you need to be mindful of the security and privacy risks associated with storing your data online. It's important to choose a reputable cloud storage provider and use strong passwords and other security measures to protect your files.

What is a coaxial cable?

A coaxial cable is a type of electrical cable that is used for transmitting signals over long distances with low signal loss. It consists of a copper conductor, which is surrounded by a layer of insulation, followed by another layer of conductive shielding and then a final outer jacket. This design helps to reduce interference and maintain the integrity of the signal being transmitted. Coaxial cables are commonly used in a variety of applications, including TV aerial cable, internet connections and networking.

What is codec?

Codec is short for 'coder-decoder' or 'compression-decompression'. It refers to a software or hardware algorithm that is used to compress and decompress digital media files, such as audio, video or images. Codecs are used to reduce the file size of digital media for efficient storage, transmission and playback. They work by analysing the data in the media file and removing redundant or unnecessary information while preserving the quality and integrity of the content. Codecs are widely used in digital media applications, such as video streaming, video conferencing and multimedia messaging. There are many different codecs available that support various media formats and compression levels.

What is file compression?

File compression is the process of reducing the size of a file by compressing its contents into a smaller package. This is done to make the file easier to store, share or send, as smaller files take up less space and require less time to transfer. File compression works by identifying and removing redundant data and by using various algorithms to encode the remaining data in a more efficient way. When a compressed file is opened, it is decompressed back into its original form, allowing it to be used as normal. File compression is commonly used for things like sending email attachments, sharing files over the internet and storing large amounts of data on a hard drive.

What is a CPU?

The CPU (Central Processing Unit) is like the brain of a computer. It's a small chip that's responsible for processing all the instructions and calculations required to run the software and perform tasks. When you use your computer, the CPU is constantly working to process all the information that's going in and out of your computer. The faster your CPU is, the more quickly your computer can perform tasks like opening programs, loading web pages and running software. The CPU is an essential component of any computer and its speed and performance can have a big impact on the overall speed and responsiveness of your system.

What is a DECT phone?

DECT (Digital Enhanced Cordless Telecommunications) is a wireless communication standard designed for voice communication over short distances. Typically used for cordless phones, DECT uses digital radio technology to provide clear and secure voice communication without interference from other wireless devices. DECT devices operate on a range of frequencies, typically around 1.9 GHz, which are reserved exclusively for DECT devices, providing high-quality voice transmission. DECT is widely used in households and businesses for cordless phones and is also used in wireless headsets, baby monitors and other applications requiring wireless voice communication over short distances.

What is defragment?

The defragment option on your Windows machine is designed to optimise your computer's hard drive data. In simple terms, your computer's hard drive is like a library of information. As files get deleted and moved around it creates pockets of empty segments on your computer's disk drive. Retrieving old files and saving new ones will take slightly longer if your hard drive is heavily fragmented. As a hard drive becomes more fragmented new files that you save may be stored in random segments of the drive, making it slower to retrieve them.

Defragmenting is a bit like rearranging the books in a library alphabetically. So go ahead and click defragment once in a while. If you're unsure how to do it, just type 'defragment' into the Windows search feature and select the hard drive you wish to optimise.

What does DPI mean?

DPI stands for 'dots per inch', which is a measurement of the resolution or clarity of an image or printed document. It refers to the number of dots that can be printed or displayed in a linear inch of the image.

The higher the DPI, the more detailed and sharper the image or document will appear. This is because a higher DPI means that more dots are used to create the image or document, resulting in finer detail and more precise colour representation.

DPI is important when working with printed materials, such as photographs or documents, as it affects the overall quality of the printed output. For example, a high-quality photograph may require a 300dpi or more in order to produce a sharp and detailed print.

What is a computer driver?

A computer driver, often referred to as a 'driver', is a small software program that allows your computer to communicate with and control a specific piece of hardware. Drivers are often necessary for hardware devices such as printers, scanners, graphics cards, and sound cards.

When a new piece of hardware is installed on a computer, the operating system may not automatically recognise it. This is where drivers come in. A driver provides the necessary instructions to the operating system to communicate with the new hardware device.

Without the proper driver, a hardware device may not work correctly. For example, if you have a printer not printing correctly, it may be due to an outdated or missing driver.

Drivers are typically provided by the hardware device manufacturer and are usually available for download from the manufacturer's website.

Devices that do not rely on the user to install drivers are often called plug 'n' play devices

What is exFAT?

exFAT stands for 'Extended file allocation table' and is a file format that is widely used. The exFAT format is particularly useful for external hard drives, USB flash drives and SD cards that need to be interchangeable between Linux, Windows and macOS.

What is FAT32?

FAT32 is the 32-bit version of the FAT file system format and stands for 'File Allocation Table32'. It was adopted in 1996 and is still used today. Due to its compatibility with both Apple macOS and Windows, the FAT32 format is often used for USB memory sticks and SD card storage.

Unfortunately FAT32 has a maximum file size of 4GB and a maximum volume size of 2TB. FAT32 has been superseded by exFAT which has no file or volume size restrictions and is also cross-platform compatible.

What is a Fax Machine?

Fax (short for facsimile) machines were a popular office device in the 80s-90s. The fax machine would scan a paper copy of a document before transmitting it to the receiving fax machine. The receiving machine then prints out a copy of the document. Fax machines could utilise an existing phone line but often had their own dedicated number.

What is a floppy drive?

A floppy disk drive (or simply 'floppy drive') is an 'old school' type of storage device that was commonly used in the past to store and transfer digital data, such as documents, photos and programs. It uses a small and flexible disk that's made of plastic and coated with a magnetic material to store data. To use a floppy disk drive, you would insert the disk into the drive, and the drive would read or write data to or from the disk using a read/write head. Floppy drives were popular in the 1980s and 1990s but have become increasingly obsolete due to their limited storage capacity and slower data transfer rates compared to modern storage devices like USB drives, external hard drives and cloud storage.

What is file formatting?

In computer terms, formatting a drive is the method used to prepare a partition ready for use. This may be required if you have purchased a new flash drive for a camera or installed a new hard drive on a computer. It is good practice to format the hard drive when installing a new operating system from scratch.

Recovering data from a formatted hard drive

It is a misconception that data cannot be recovered after it has been formatted. A basic file format, sometimes called 'Quick format', erases the drive's index 'address book', without which you can no longer see the files. However, the files are still there until they are overwritten with new data. Data recovery software is required if you have accidentally formatted a drive that contains files that you still need. Recovery software like Cleverfiles is what we would recommend and is compatible with both Mac and PC. If you have performed a 'Secure format,' then the content on the drive will be overwritten to ensure it is non-retrievable. This method should be used if you are selling a device or transferring ownership. Secure file formatting can take quite a while to do, depending on the size of your drive and the speed of your device. If your disk format was performed in seconds, it was likely to have been a 'Quick format' version.

Note there is no guarantee of retrieving data, so make sure you know what you are doing before performing a disk format.

What is a Gigabyte 'GB'?

Gigabyte, often abbreviated to 'GB' is a unit of digital storage. One gigabyte is equal to 1,000 megabytes, or one billion bytes.

In simpler terms, a gigabyte represents the amount of storage space available to store digital files such as documents, photos, music and videos on a computer or other device. The larger the amount of storage space in gigabytes, the more files and data that can be stored on the device.

For example, a typical music album may take up about 100 megabytes of storage space, while a high-definition movie can require several gigabytes. The storage capacity of a device is often measured in gigabytes, with larger devices such as external hard drives or cloud storage services offering terabytes (TB) or even petabytes (PB) of storage space.

What is a computer hard drive?

A computer hard drive can be used to store large amounts of data, like photos, music, files and videos, as well as the computers operating system. A hard drive may also be referred to as a 'hard disk drive' (HDD) or (HD) for short. A computer must have at least one form of hard drive to function but can have multiple hard drives if additional storage is required. Additional drives are often external to the computer, but a large computer may have multiple internal drives. See 'SSD' for alternative hard drive replacement

What is Mac OS Extended Journaled?

Mac OS Extended Journaled is a disk format used on Apple computers operating macOS 10.12 or earlier. It uses the Mac format Journaled HFS Plus to protect the integrity of the hierarchical file system. Choose OS Extended Journaled if you don’t need an encrypted or case-sensitive format. The APFS file format is used on macOS 10.13 onwards

What is a memory stick?

A memory stick is a small compact device to store digital data, with a similar weight and size to a house key. They are a very cost-effective way of adding simple extra storage to a computer. Primarily memory sticks are used for transferring data from one device to another.

For maximum compatibility between devices, format the memory stick in exFAT. This will ensure it's compatible with Apple macOS and Windows operating systems. Prices vary, but you can expect to pay from £4 for a 16Gb stick to £35 for a 256Gb stick. Memory sticks can look identical but offer significantly different performances. Make sure you compare the transfer speed when comparing prices.

Memory sticks are also referred to as thumb drives, pen drives, flash drives and USB sticks.

USB memory stick

What is a motherboard?

A motherboard is the main circuit board of a computer system. It connects and controls all the different parts of the computer, such as the CPU (the brain of the computer), the RAM (where the computer stores its temporary data), and the hard drive (where the computer stores its long-term data). It also provides slots and connectors for other components like graphics cards and sound cards. In essence, the motherboard is like the central nervous system of a computer, allowing all the different parts to communicate and work together effectively.

What is a computer mouse | trackpad?

A mouse and a trackpad are devices used to control the movement of the cursor on a computer screen. The mouse is a small device that is placed on a flat surface and moved around to control the cursor. It usually has one or more buttons that can be clicked to perform actions such as selecting or opening items. A trackpad, on the other hand, is a flat surface that is either built into a laptop or operates as a stand alone device. It allows you to control the cursor by moving your finger across the surface and you can click or tap the surface to perform actions. They are both essential items of a computer system.

What is NTFS?

NTFS is a file format created by Microsoft in 1993, and it's compatible with all Windows operating systems. However, the NTFS file format is not compatible with Apple macOS and will be restricted to a read-only feature. The file format FAT32 or exFAT should be used when data needs to be exchanged between Mac and PCs.

What is an operating system?

An operating system is like the boss of your computer or mobile device. It manages all the different parts of your device, such as the screen, keyboard, memory and storage and makes sure they work together properly. The operating system also runs other programs and applications, such as web browsers, games and word processors. It provides a way for you to interact with your device, such as by clicking on icons or typing on a keyboard and allows you to save and retrieve files from storage. Just like a boss delegates tasks to employees, an operating system handles the tasks and resources of your device, making it possible for you to use your device the way you want.

What is a hard disk drive partition?

A hard disk drive partition is a way of dividing one physical drive into smaller volumes. All hard drives require at least one partition, this can be 100% of the drive. Alternatively, you could add a second partition and allocate a percentage of the space to it.

Why would I create a hard drive partition?

Creating a second drive partition can help avoid accidentally deleting data. It can also be used as a backup drive. Most new computers come with a built-in backup of the original operating system. This information is stored in a second partition on the computer's hard drive. So, if you accidentally delete or corrupt the operating system, you can reinstall it using the data on the built-in recovery partition.

Creating a partition on a hard drive can result in loss of data if done incorrectly. Make sure you have a backup copy and understand what you are doing before proceeding.

What is a PC?

A PC, or personal computer, is a type of electronic device that is designed for individual use. PCs are used for a wide variety of purposes, including web browsing, word processing, gaming, multimedia applications and more. They are highly customisable and can be configured to meet specific needs, from basic home use to high-performance gaming or professional work.

What is a PDF?

PDF stands for 'Portable Document Format', which is a file format that is used to present and exchange documents in a way that is independent of software, hardware and operating systems. In other words, a PDF file can be viewed and printed on almost any device, regardless of the software or operating system that is being used.

PDF files are commonly used for online documents, forms and manuals. They are particularly useful when it is important to preserve the formatting and layout of a document, such as when sharing a document that includes images, tables, or other graphical elements.

Once a PDF file is created, it can be opened and viewed using a PDF reader like Adobe Acrobat Reader

What does the term Plug 'n' Play mean?

Plug 'n' Play is a term used to describe technology or devices that are designed to be easy to use and require little or no setup. The term Plug 'n' Play means that you can simply plug a device into a compatible computer or another device and it will be automatically detected and configured without any additional setup required.

This type of technology is often used for peripherals such as printers, scanners and other devices that connect to a computer. For example, if you have a Plug 'n' Play printer, you can plug it into your computer's USB port and it will be automatically detected and installed by the operating system without you having to download and install any additional drivers or software.

What is a quad-core processor?

A quad-core processor is a single microchip that has 4 individual processing cores. A quad-core CPU can process instructions using all 4 cores simultaneously, a method known as multitasking. A modern high-spec computer like a MAC Pro may have as many as 28 cores.

What is a Qwerty keyboard?

QWERTY is a keyboard layout that is commonly used in English language keyboards. The name comes from the first six letters on the top row of the keyboard, from left to right. The QWERTY layout was designed in the 1870s for typewriters and was intended to minimise the likelihood of the mechanical arms of adjacent keys jamming together. The layout has since become widely used for computer keyboards, and while there have been alternative keyboard layouts developed, such as Dvorak and Colemak, QWERTY remains the most commonly used layout today.

What is RAM?

RAM stands for (Random Access Memory). It is a type of computer memory that is used to temporarily store data and programs that are currently in use. Unlike a computer's hard drive or solid-state drive, which provides long-term storage, RAM is volatile memory that is designed for short-term storage and rapid access. When a program or application is opened on a computer, it is loaded into RAM so that it can be quickly accessed and processed by the computer's CPU (Central Processing Unit). The amount of RAM a computer has can have a significant impact on its performance, as more RAM allows the computer to run more programs and perform more tasks simultaneously without slowing down. However, once the computer is shut down, any data stored in RAM is lost, so it is important to save important data to a hard drive or another storage device before shutting down the computer.

What is ROM (Read only memory)?

ROM, or Read-Only Memory, is a type of computer memory that is used to store data permanently. Unlike other types of memory, such as RAM, ROM is non-volatile, which means that it retains its data even when the computer is turned off. As its name suggests, data can be read from ROM, but not written to it, hence it is referred to as read-only. ROM is often used to store firmware, such as the basic input/output system (BIOS) on a computer, which is essential for the system to start up. Other types of data that may be stored in ROM include operating system boot code, application software and other critical system information.

What is a Safe Mode?

Safe Mode is a troubleshooting mode that can be used to diagnose and fix problems with a computer or other electronic device. When a device is started in Safe Mode, it loads only the most essential software and drivers and disables any third-party software or drivers that may be causing problems.

Safe Mode is often used when a device is experiencing issues such as crashes, freezes, or startup problems. By starting the device in Safe Mode, you can isolate the issue and determine whether it is being caused by a problem with the device's software or hardware.

In Safe Mode, the device may look and function differently than it does in normal mode. For example, the screen resolution may be lower, and certain features may be disabled. This is because Safe Mode is designed to load only the most essential software and drivers in order to help diagnose and fix problems.

To start a device in Safe Mode, you may need to press a specific key or combination of keys during startup. The exact method for starting a device in Safe Mode can vary depending on the device and the operating system that is being used. Once the device is in Safe Mode, you can run diagnostics, uninstall problematic software or drivers, and perform other troubleshooting steps to fix the issue.

What is an SSD?

SSD stands for (solid state drive). It's a faster and more reliable method of storing digital data on a computer. For decades, computers have stored information on hard disk drives (HDD). Traditional HDDs are significantly cheaper in comparison to the equivalent SSD so they still have a place in the market.

What is the benefit of using SSD?

Traditional hard disk drives contain many moving parts including a motor that needs to rotate between 5400 and 7200rpm. The HDD's motor needs to reach its operating speed before data can be accessed. This produces a delay in reading and writing data to the disk. The only way to avoid this delay is to switch off the HDD energy-saving features, which will increase power consumption and reduce the lifespan of the drive. An SSD uses flash memory which means data is stored on microchips, avoiding the need for any moving parts. Without the need for mechanical components, SSDs can operate more efficiently, saving power and resulting in a more durable component.

What does unzip mean?

Unzip refers to the process of extracting the contents of a compressed or zipped file on a computer. A compressed or zipped file is a file that has been compressed to take up less storage space or make it easier to transfer over the internet. To access the contents of a compressed file, it needs to be unzipped, which involves using a software program that can extract the contents of the file and restore them to their original size and format. The unzipped contents can then be used, such as opening an image, document, or video file, or installing a software program. Many computers have built-in zip and unzip functionality, while there are also several third-party software programs available for managing compressed files.

What does uptime mean?

Uptime is a definition used to represent the active duration time of a computer or network device. Uptime is often used to display hardware reliability, this might be shown as a percentage like 99.999% or a time frame in days, hours, minutes and seconds. If you have a website or a device with a static IP address, perhaps a security camera you can monitor the up time of the device for free with uptime robot. We have been using them for years and highly recommend this service.

What is a USB?

USB stands for Universal Serial Bus. It is a standard protocol used for connecting various devices to a computer. USB provides a simple and easy way to transfer data between devices such as flash drives, keyboards, mice, printers and smartphones. USB is a widely adopted technology due to its ease of use, portability and versatility. It allows devices to be connected and disconnected without having to restart the computer or install additional hardware. USB also provides power to devices that require it, making it an essential technology for modern computing.

What is a USB dongle (pen drive)?

A USB dongle, also known as a pen drive or USB flash drive, is a small portable storage device that connects to a computer via a USB port. It allows users to store and transfer digital files, such as documents, photos, videos and music, between different computers and devices. USB dongles are compact and easy to use, making them a popular choice for people who need to carry important files with them on the go. They are often used for backup, file sharing and transporting data between computers.

What is a Wi-Fi printer?

A Wi-Fi enabled printer is a type of printer that can connect to a wireless network, so you can print from your computer, laptop, or mobile device without having to connect them to the printer physically. You can send a print request to the printer over the Wi-Fi network, and the printer will receive it and print out your document or image. This can be very convenient if you have multiple devices that need to use the same printer or if you don't want to have cables running from your devices to the printer. Wi-Fi printers are becoming more common and are often used in home offices, small businesses or other places where multiple people need to print from different devices.

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