IT Glossary
Key Terms To Know In The IT Industry

High Availability Cluster

A group of computers that work together to ensure that services remain available even if one or more of the computers fail.

You will find this term commonly used in Networking, Systems Design

High Dynamic Range (HDR)

A technology used in imaging and photography to reproduce a greater range of luminosity than what is possible with standard digital imaging or photographic techniques.

You will find this term commonly used in Multimedia, Photography

High Dynamic Range Imaging (HDRI)

A technique used in imaging and photography to reproduce a greater range of luminosity than what is possible with standard digital imaging techniques.

You will find this term commonly used in Multimedia, Design

High Efficiency Video Coding (HEVC)

Also known as H.265, a video compression standard designed to substantially improve coding efficiency compared to its predecessor (H.264), enabling higher quality video streaming over the same bandwidth.

You will find this term commonly used in Multimedia, Broadcasting

High-Bandwidth Digital Content Protection (HDCP)

A form of digital copy protection developed to prevent copying of digital audio and video content as it travels across connections.

You will find this term commonly used in Multimedia, Security

High-Definition (HD)

A term used to describe video of higher resolution than standard definition, often with a resolution of 1280x720 pixels or higher.

You will find this term commonly used in Multimedia

High-Level API

An application programming interface that abstracts the complexity of a system into a simpler interface, making it easier for developers to program applications.

You will find this term commonly used in Programming, Software Development

High-Level Assembly (HLA)

An assembly language that includes some high-level language features, designed to ease the development of assembly language applications.

You will find this term commonly used in Programming

High-Level Language

A programming language that abstracts the details of the computer hardware, allowing them to be more readable and closer to human language.

You will find this term commonly used in Programming

High-Level Programming Language

A programming language with strong abstraction from the details of the computer. It allows programmers to write programs that are more readable and easier to debug.

You will find this term commonly used in Programming

High-Level Shader Language (HLSL)

A proprietary shading language developed by Microsoft for use with the DirectX API. It's used for writing shaders that determine the final look of 3D scenes by controlling the graphics pipeline.

You will find this term commonly used in Game Development, Graphics

High-Level Synthesis (HLS)

The process of converting high-level programming languages (like C, C++) into hardware description languages, which are used to create digital circuits.

You will find this term commonly used in Hardware, Programming

High-Order Bit

The bit in a binary number that represents the greatest order of magnitude. In an 8-bit byte, this would be the leftmost bit.

You will find this term commonly used in Computing

High-Order Function

A function that does at least one of the following: takes one or more functions as arguments (i.e., procedural parameters), returns a function as its result.

You will find this term commonly used in Programming

High-Pass Filter

In computing and signal processing, a filter that passes signals with a frequency higher than a certain cutoff frequency and attenuates signals with lower frequencies.

You will find this term commonly used in Multimedia, Audio Processing

High-Performance Parallel Interface (HIPPI)

A computer bus for the transfer of large blocks of data at speeds suitable for supercomputers and complex scientific applications.

You will find this term commonly used in Networking, Hardware

HMAC (Hash-Based Message Authentication Code)

A specific type of message authentication code (MAC) involving a cryptographic hash function and a secret cryptographic key. It is used to verify both the data integrity and the authenticity of a message.

You will find this term commonly used in Security, Cryptography

HMAC Authentication

A technique for verifying the integrity and authenticity of a message with a secret key, using Hash-Based Message Authentication Code.

You will find this term commonly used in Security, Cryptography

Holographic Storage

A type of data storage technology that uses the three dimensions of space for data storage instead of the two-dimensional surfaces of conventional storage media.

You will find this term commonly used in Hardware, Storage

Home Page

The initial or main web page of a website or a browser.

You will find this term commonly used in Web Development

Homogeneous Network

A network environment in which all the computers and devices run on the same operating system or platform, often simplifying management and compatibility issues.

You will find this term commonly used in Networking

Homomorphic Encryption

A form of encryption that allows computation on ciphertexts, generating an encrypted result which, when decrypted, matches the result of operations performed on the plaintext.

You will find this term commonly used in Cryptography

Honeynet

A network set up with intentional vulnerabilities; its purpose is to invite attack, so that an attacker's activities and techniques can be studied and that information used to increase network security.

You will find this term commonly used in Security, Cybersecurity

Honeypot

A security mechanism set to detect, deflect, or, in some manner, counteract attempts at unauthorized use of information systems. Typically, it consists of a computer, data, or a network site that appears to be part of a network but is actually isolated and monitored.

You will find this term commonly used in Security, Cybersecurity

Horizontal Scaling

The process of adding more machines or setting up a cluster of machines to share the load more efficiently.

You will find this term commonly used in Cloud Computing, Systems Design

Host

A computer or other device connected to a computer network; often, it is a computer that manages network resources. For example, a file server is a host that stores files, and a web server is a host that stores websites.

You will find this term commonly used in Networking

Host File

A computer file used by an operating system to map hostnames to IP addresses.

You will find this term commonly used in Networking

Host Header

A type of HTTP header that specifies the domain name of the server (website) to which the request is being sent. It is used for routing requests to multiple domains hosted on a single IP address.

You will find this term commonly used in Networking, Web Development

Host Intrusion Prevention System (HIPS)

A security solution that monitors a single host for suspicious activity by analyzing events occurring within that host.

You will find this term commonly used in Security, Cybersecurity

Host Operating System

In virtualization, the OS that runs on the physical hardware and hosts the virtual machines.

You will find this term commonly used in Operating Systems, Virtualization

Host-Based Security System (HBSS)

A framework used in information security management that secures individual devices from threats, often including antivirus, firewall, and intrusion detection systems.

You will find this term commonly used in Security, Cybersecurity

Host-to-Host Communication

In networking, the process by which two hosts (computers, servers, etc.) communicate with each other over a network.

You will find this term commonly used in Networking

Hosted Application

Software as a Service (SaaS) that is accessed over the internet and hosted in a cloud environment, rather than on-premises.

You will find this term commonly used in Cloud Computing, Software as a Service

Hosted Database

A database that is hosted on a remote server, allowing users to access it over the Internet, typically managed by a third-party service provider.

You will find this term commonly used in Cloud Computing, Databases

Hosted Git

A service that provides Git repository hosting which is accessible over the internet. Popular hosted Git services include GitHub, GitLab, and Bitbucket.

You will find this term commonly used in Software Development

Hosted Service

A service provided over the Internet or through a dedicated network.

You will find this term commonly used in Cloud Computing, Networking

Hosted Services

Web services or applications that are hosted by a provider, often in the cloud, allowing customers to access software over the internet.

You will find this term commonly used in Cloud Computing

Hostname

The unique name by which a device is known on a network, used to identify the device in various forms of electronic communication.

You will find this term commonly used in Networking

Hot Deployment

The process of adding new components (such as software updates or new configurations) to a running system without needing to restart it.

You will find this term commonly used in Software Development

Hot Fix

A quick repair job for a piece of programming during the software maintenance process.

You will find this term commonly used in Software Development, Security

Hot Standby

A redundancy approach where a backup system runs simultaneously with the primary system and can take over immediately without loss of service if the primary system fails.

You will find this term commonly used in Systems Design, Networking

Hot Swapping

Replacing or adding components without stopping or shutting down the system.

You will find this term commonly used in Hardware, Computing

Hotfix

A quick repair job for a piece of programming during the software maintenance process.

You will find this term commonly used in Software Development

Hotlink Protection

A security measure used to prevent other websites from directly linking to files (as images, video, etc.) on your website, which can consume bandwidth and server resources.

You will find this term commonly used in Web Development, Security

Hotspot

A physical location where people may obtain Internet access, typically using Wi-Fi, via a wireless local area network (WLAN) with a router connected to an internet service provider.