IT Glossary: Technical Terms Clearly Explained

.NET is Microsoft’s open-source platform for building web, desktop, mobile and cloud applications; C# is the primary language in the .NET ecosystem.

Fifth generation of mobile networks with peak speeds, minimal latency and massive device connectivity – the foundation for IoT, autonomous driving and Industry 4.0.

An experimental method in which two variants (A and B) of a webpage, app or feature are tested in parallel to determine the better version based on data.

Design of software and websites so they are usable by everyone, including people with disabilities. From 2025 mandatory in the EU for many digital offerings.

Iterative approach to software development with short cycles, regular feedback and continuous improvement – instead of rigid planning and long waterfall phases.

Systems that simulate human intelligence – learning, problem-solving, pattern recognition. Used in business for automation, analysis, chatbots and forecasting.

Retrieval-Augmented Generation – an AI approach where language models use company-specific documents to give accurate, factual answers.

A precise, finite sequence of instructions for solving a problem – the basis of all software, from search results to AI decisions.

An open-source framework developed by Google, based on TypeScript, for building scalable single-page applications (SPAs) and enterprise web applications.

Application Programming Interface – an interface through which different software systems communicate and exchange data.

A central entry point (reverse proxy) that receives, routes, secures and monitors all incoming API requests – the gateway to your microservices.

Creating applications for smartphones, tablets and desktop – from native iOS/Android apps to cross-platform (Flutter/React Native) and PWAs.

Technology that overlays digital content onto the real environment – via smartphone camera, tablet or AR glasses for visualisation, navigation and training.

Authentication verifies a user's identity. OAuth 2.0 enables secure third-party access; MFA adds security through multiple factors.

Use of software to run recurring tasks without manual intervention – from RPA and workflow automation to AI-driven process optimisation.

Amazon's leading cloud platform with over 200 services for compute, storage, AI, databases and more – the basis for modern web apps and AI projects.

Microsoft's comprehensive cloud computing platform with over 200 services for infrastructure, databases, AI, DevOps and more – the enterprise cloud solution.

The server-side part of an application: business logic, data processing, API provision and database access – the invisible foundation of every piece of software.

Strategies and measures for backing up data (backup) and for restoring IT operations after failures or disasters (disaster recovery).

The maximum amount of data that can be transmitted over a network connection in a given time – critical for cloud applications and digital business processes.

An energy-saving short-range wireless protocol (part of the Bluetooth standard from version 4.0), optimized for IoT devices, wearables and sensor networks.

Decentralised, tamper-resistant database where transactions are stored in linked blocks – basis for cryptocurrency, supply chain and smart contracts.

An open-source CSS framework (originally from Twitter) with ready-made components and a responsive grid system for fast web development.

A bug is an error in software; debugging is the process of finding and fixing it. Modern tools like debuggers, logging and error tracking make finding faults easier.

Technologies and strategies for analysing business data to support better decisions – with dashboards, reporting, data warehousing and visualisation.

Storing frequently needed data in a fast, easily accessible location to reduce access times and offload backend systems.

Security mechanism to tell humans and bots apart – from distorted text and image puzzles to invisible behaviour analysis.

A globally distributed network of servers (edge servers) that cache and deliver content such as images, videos and web pages close to the user.

AI-powered dialogue systems that answer user requests automatically – from rule-based FAQ bots to LLM-based assistants with natural language understanding.

Continuous Integration / Continuous Deployment – automated processes to test and deliver software updates for faster releases with high quality.

Provision of IT resources (servers, storage, databases, AI) over the internet on demand – instead of your own hardware. Flexible scaling and pay-as-you-go.

Software architecture designed for the cloud: microservices, containers, dynamic scaling and declarative APIs.

Content Management System – software to create and manage website content without programming. From WordPress and TYPO3 to headless CMS like Strapi.

The systematic review of source code by other developers to find defects, ensure quality and share knowledge within the team.

A browser security mechanism that controls which websites may access resources on other domains (origins) using special HTTP headers.

Customer Relationship Management – software for central management of customer relationships, sales processes and marketing campaigns for better retention.

Development approach with one codebase for multiple platforms (iOS, Android, web). Frameworks like Flutter and React Native deliver near-native performance.

Cascading Style Sheets – the stylesheet language that defines the look of websites: layout, colours, fonts, animations and responsive design.

Protection of IT systems, networks and data from digital attacks – with measures such as penetration testing, encryption, firewalls and security awareness.

The process of moving data between storage systems, databases, formats or applications – e.g. during system changes, cloud migrations or mergers.

Organised collection of data that can be stored and queried electronically. Relational databases use tables; NoSQL uses flexible models.

A cyber attack in which thousands of compromised devices send huge numbers of requests to a target system to overwhelm it and make it unavailable.

Programming language and IDE for Windows applications (Embarcadero). Many companies still run Delphi legacy systems that need modernisation.

A documented set of reusable UI components, design tokens, patterns and guidelines that ensures a consistent user experience across all digital products.

Culture and practice that connects development (Dev) and IT operations (Ops) – for faster releases, better quality and higher stability.

The fundamental change of business models, processes and corporate culture through the strategic use of digital technologies – far more than mere digitization.

The Domain Name System (DNS) translates human-readable domain names (e.g. google.com) into machine-readable IP addresses (e.g. 142.250.185.99) – the internet’s phone book.

Technology to package applications with all dependencies. Containers enable consistent deployments and are the basis for Kubernetes.

The web address of a site (e.g. example.com). Domains consist of name and top-level domain and are the basis for branding and reachability.

A software design approach that puts the business domain at the center and, through close collaboration between developers and domain experts, leads to practical, maintainable solutions.

Edge computing moves data processing from the central data centre to the edge of the network – closer to the devices and users that produce the data.

Software that replicates another system – e.g. an Android emulator on a PC. Essential for app development and testing on various devices.

Encryption where data stays encrypted from sender to recipient – even the service provider cannot read the content.

Enterprise Resource Planning – integrated business software for finance, logistics, production, HR and more. Well-known systems: SAP, Odoo, Microsoft Dynamics.

Firebase is a Google-operated Backend-as-a-Service platform that provides developers with ready-made backend services such as database, authentication and hosting.

Security system that monitors and filters network traffic by rules. Firewalls protect internal networks from unauthorized access and attacks.

Open-source framework from Google for building cross-platform apps. One Dart codebase for iOS, Android, Web and Desktop.

The visible part of an application – layout, design, navigation and interactions. Modern frameworks: React, Angular, Vue.js and Next.js.

General Data Protection Regulation – EU-wide rules on processing personal data, affecting how software stores, processes and handles user data.

AI that creates new content – text (ChatGPT), images (DALL-E, Midjourney), code (GitHub Copilot). GenAI is changing content creation, customer service and software development.

Git is a version control system for tracking code changes. GitHub and GitLab are platforms for collaborative development with code review and CI/CD.

Go (also Golang) is a statically typed programming language developed by Google, known for high performance, simplicity and first-class concurrency.

Google Cloud (GCP) is Google's cloud computing platform, providing infrastructure, platform and software services for organizations of all sizes.

Query language for APIs developed by Facebook/Meta; enables precise data requests and reduces over- and under-fetching compared to REST.

Content management system without its own frontend. Content is delivered via APIs and can be displayed on websites, apps and any channel.

HyperText Markup Language – the markup language for web pages. HTML defines structure and content: headings, paragraphs, links, images, forms and more.

Hypertext Transfer Protocol – the communication protocol of the web. HTTPS is the encrypted variant with TLS/SSL and the standard for all sites.

App built with web technologies (HTML, CSS, JS) inside a native container. Runs on multiple platforms but doesn’t always match native performance.

Internationalization (i18n) prepares software for multiple languages. Localization (l10n) adapts content, formats and cultural conventions to a specific target region.

Infrastructure as Code (IaC) is the practice of defining and managing IT infrastructure – servers, networks, databases – through machine-readable configuration files instead of manual processes.

An interface (API/interface) defines how two software systems communicate. Integration is the process of connecting those systems and exchanging data automatically.

Ionic is an open-source framework for building cross-platform mobile and web apps with web technologies such as HTML, CSS and JavaScript/TypeScript.

Connecting physical devices to the internet. IoT enables data collection, remote control and automation in Industry 4.0, smart home and logistics.

An IT audit is a systematic review and assessment of an organization's IT infrastructure, IT processes and IT security against defined standards and best practices.

IT consulting is the strategic and technical advice to companies on IT decisions – from technology selection and architecture planning to digital transformation.

IT outsourcing is the contracting out of IT tasks, processes or entire IT departments to external service providers – from software development to infrastructure management.

Java is an object-oriented, platform-independent programming language that has been among the world’s most used since 1995 – especially in enterprise and Android development.

The main language of the web – runs in the browser and on the server (Node.js). Foundation for React, Angular, Vue.js and Next.js.

JavaScript Object Notation – a lightweight format for structured data. The de facto standard for REST APIs and config files.

Agile method to visualize and control work on a board with columns (To Do, In Progress, Done) and WIP limits for continuous flow.

Modern language from JetBrains; Google’s preferred language for Android. Interoperable with Java, more concise and safer.

Open-source platform for container orchestration. Automates deployment, scaling and management of containerized applications in clusters.

Local Area Network – a local network connecting devices in an office or building. WLAN is the wireless variant over Wi-Fi.

Laravel is an open-source PHP framework for building modern web applications, known for elegant syntax, rich features and a strong ecosystem.

Updating legacy systems through refactoring, migration or gradual replacement. Goal: preserve business value while improving maintainability and security.

Older software still in production that may be technically outdated. Often business-critical but hard to maintain, extend and secure.

Load balancing distributes incoming network traffic across multiple servers to optimize utilization, ensure resilience and minimize response times for users.

Development platforms with visual building blocks instead of code. Enable fast prototypes and simple applications without developer expertise.

Subfield of artificial intelligence where algorithms learn from data and recognise patterns without being explicitly programmed.

Magento (Adobe Commerce) is a powerful open-source e-commerce platform for building and running professional online shops with extensive customization options.

Managed services are the outsourcing of IT operations to an external provider who proactively monitors, maintains and optimizes systems.

A message queue is an asynchronous communication mechanism where messages are stored in a queue until the consumer can process them.

Architecture pattern where an application consists of many small, independently deployed services that communicate via APIs.

Middleware is software that acts as a mediation layer between applications, systems or services and enables their communication and data exchange.

MongoDB is a document-oriented NoSQL database that stores data in flexible JSON-like documents (BSON) and is well suited for agile development and large data volumes.

Monitoring observes the availability and performance of IT systems in real time; logging is the structured recording of events and errors.

Software architecture where all functionality is in a single, cohesive codebase and one shared deployment artefact.

Multi-tenancy is an architecture principle where a single software instance serves multiple customers (tenants) while keeping their data strictly separated.

The first working version of a product with only core features, to validate a business idea quickly in the market.

MySQL is a relational open-source database management system (RDBMS) that uses SQL for data management and is the world's most widely used open-source database.

App developed specifically for one operating system (iOS or Android) in its native language, with full access to all device features.

Outsourcing of software development to teams in geographically close countries with similar time zones and cultural proximity.

Next.js is a React-based full-stack framework for web development that provides server-side rendering, static site generation and API routes out of the box.

Node.js is a cross-platform JavaScript runtime that allows running JavaScript outside the browser on the server.

Umbrella term for non-relational databases that offer flexible data models, horizontal scaling and high performance for large data volumes.

Modular open-source ERP suite that combines CRM, e-commerce, accounting, inventory and more in one integrated platform.

Outsourcing of software development to teams in distant countries with significantly lower labour costs, e.g. India, Vietnam or the Philippines.

Software and IT infrastructure run in your own data centre or on your own servers, rather than in the cloud.

Electronic commerce over the internet, typically via an online shop that sells products or services digitally.

Software whose source code is publicly accessible and may be viewed, used, modified and redistributed by anyone.

An ORM (Object-Relational Mapping) maps database tables to objects in a programming language and replaces SQL with object-oriented methods.

Penetration testing (pentest) is an authorized, simulated cyber attack on an IT system to find security gaps before real attackers can exploit them.

Phishing is a social-engineering method where attackers try to steal sensitive data such as passwords or payment details via fake emails, websites or messages.

PHP (PHP: Hypertext Preprocessor) is a server-side scripting language designed for web development and used on over 75% of all websites with known server technology.

PostgreSQL is a powerful, object-relational open-source database management system known for reliability, extensibility and SQL standards compliance.

A feasibility demonstration showing that a technical idea or approach works in practice before larger investment is made.

Early version of a product or application that visualises design and interaction before actual development starts.

Short messages sent from an app or website directly to the user’s device, even when the app is not open.

Web application that behaves like a native app: installable, offline-capable and with push notifications, but built for the browser.

Versatile, easy-to-learn programming language that is among the most used worldwide for AI, data science, web development and automation.

Systematic process of checking software for defects, security issues and quality requirements through manual and automated tests.

Ransomware is malware that encrypts data or systems and demands a ransom for decryption.

Rate limiting is a technique that limits how many requests a client may send to an API or service within a given time window.

JavaScript library from Meta for interactive web UIs (React) and native mobile apps (React Native) with a shared codebase.

Redis is an open-source in-memory data store used as a database, cache and message broker, known for extremely low latency.

Systematic improvement of the internal structure of existing code without changing its external behaviour.

The requirements specification describes WHAT the client wants (requirements). The functional specification describes HOW the contractor will implement it (solution). Both are central documents in software development.

Web design approach where layout and content automatically adapt to the screen size of the device.

Architectural style for web interfaces that uses standard HTTP methods (GET, POST, PUT, DELETE) to exchange data between systems.

Technology where software robots automate repetitive, rule-based business processes that were previously done manually on a computer.

Software as a Service (SaaS) is a cloud-based delivery model where applications are used over the internet and paid by subscription – without local installation or your own servers.

Agile framework for software development that works in short iterations (sprints) and uses defined roles, events and artefacts for transparency, inspection and adaptation.

An SDK (Software Development Kit) is a package of tools, libraries, documentation and sample code that makes it easier for developers to build software for a specific platform or service.

SEO (Search Engine Optimization) covers all measures to improve a website's visibility in the organic search results of Google and other search engines.

Cloud model where the provider fully manages infrastructure and code runs only when needed – billing is per invocation instead of per server.

Shopware is a German-developed e-commerce platform that enables businesses to build and run powerful, customizable online shops.

An SLA (Service Level Agreement) is a contract between a provider and a customer that defines measurable quality criteria for a service – e.g. availability, response times or support level.

Software leasing lets companies finance custom-developed software in monthly instalments instead of paying full development cost upfront.

All activities to fix defects, adapt, optimise and preventively maintain existing software after it goes live.

Systematic analysis, stabilisation and further development of failed or struggling software projects – when in-house development or the current vendor has failed.

A Single Page Application (SPA) is a web application that loads only one HTML page and fetches content dynamically via JavaScript – without full page reloads, enabling an app-like experience.

A sprint is a fixed-length iteration (usually 2 weeks) in Scrum in which the development team delivers a defined set of work and a working software increment.

SQL (Structured Query Language) is the standardized query language for relational databases. With SQL you can query, insert, update, delete data and manage database structures.

Microsoft SQL Server is a relational database management system (RDBMS) used to store, manage and analyse structured data in organizations of all sizes.

SSL (Secure Sockets Layer) and its successor TLS (Transport Layer Security) are cryptographic protocols that encrypt communication between browser and server and verify website identity with certificates.

SSR (Server-Side Rendering) generates HTML on the server on each request. SSG (Static Site Generation) generates all HTML at build time. Both improve load time and SEO compared to client-only rendering.

A staging environment is a production-like test environment where new software versions are tested under real conditions before being deployed to production.

Swift is Apple’s modern, safe and performant programming language for building apps for iOS, macOS, watchOS and tvOS – the successor to Objective-C.

Symfony is an open-source PHP framework based on established design patterns that enables building robust, scalable and maintainable web applications in enterprise environments.

Tailwind CSS is a utility-first CSS framework that provides predefined utility classes so developers can style interfaces directly in the HTML markup without writing custom CSS.

Test-Driven Development (TDD) is a software development approach where you first write a failing test, then the minimal code to pass it, then refactor – the Red-Green-Refactor cycle.

Technical debt (technical debt) describes the hidden cost of taking shortcuts in software development – at the expense of long-term code quality.

Systematic review and assessment of a company’s technical infrastructure, software architecture and IT organisation – typically before investments, acquisitions or partnerships.

Terraform is an open-source tool from HashiCorp for Infrastructure as Code (IaC) with which cloud infrastructure can be defined declaratively, versioned and provisioned automatically.

Time-to-market (TTM) is the time from the first idea to the product’s market launch. In software, short TTM is a key competitive advantage.

Two-factor authentication (2FA) is a security method where users confirm their identity with two different factors – typically password (knowledge) plus a second factor such as a one-time code (possession) or fingerprint (biometrics).

TypeScript is a programming language from Microsoft that adds static typing to JavaScript. It improves code quality and catches errors early – especially in large projects.

TYPO3 is an open-source enterprise content management system (CMS) that stands out for multilingual support, multi-site capability and high customizability for medium and large web projects.

UX (User Experience) design shapes the overall experience of an application; UI (User Interface) design shapes the visual surface. Together they make software intuitive, appealing and effective.

A vector database is a specialized database system that stores high-dimensional vectors (embeddings) and enables efficient similarity search – a key technology for AI applications like RAG and semantic search.

Vendor lock-in is when a company depends on a specific technology vendor so that switching to another would be very costly, difficult or risky.

A VPN (Virtual Private Network) is an encrypted network connection that enables secure data exchange over public networks – as if you were directly on the local company network.

Vue.js is a progressive JavaScript framework for building user interfaces. It combines a low barrier to entry with the power of a full framework for single-page and complex web applications.

Web development covers the conception, design and programming of websites, web applications and web APIs – from simple landing pages to complex SaaS platforms.

A webhook is an HTTP callback where one system sends a notification to a URL when a defined event occurs – real-time data exchange without constant polling.

WebSocket is a protocol that provides a persistent, bidirectional connection between client and server. Unlike HTTP, both sides can send data at any time without starting a new request.

Whitelabel is software or a service developed by one vendor and licensed to others who sell it under their own brand and design to their customers.

WiFi 6 (802.11ax) is the current WLAN standard, offering significantly higher speeds, better performance with many simultaneous devices and lower power consumption than WiFi 5.

A wireframe is a simplified, schematic sketch of a user interface showing structure and layout. A mockup is a more detailed visual draft with colours, typography and images – close to the final design.

WordPress is an open-source content management system (CMS) and the world's most used website platform, powering over 40% of all websites – from simple blogs to complex corporate sites.

Zero Trust is a security model that does not trust any user, device or network by default – not even inside the corporate network. Every access is authenticated, authorized and continuously verified.

Zero-downtime deployment is a deployment strategy where software updates are applied without interrupting the running service – users do not notice the update.