| Typical home broadband bandwidth | 100–500 Mbps (Federal Communications Commission broadband benchmarks) |
| What 'https' signals | Encrypted connection |
| Latency considered low for video calls | Under 150 ms (ITU-T G.114 recommendation) |
| Cache clearing effect | Slower first reload, cleared stored data |
| Firmware update delivery | Over-the-air (OTA) or via USB |
Why These Words Keep Showing Up
Tech terminology has escaped the server room. Words like API, bandwidth, and firmware now appear in app update notices, news headlines, and everyday conversations — usually without explanation. This reference guide defines the terms you encounter most, in plain language, so you can follow along with confidence rather than quietly guessing.
If you've ever wondered why your phone asks to update its firmware, or what it means when a website says it's using a cache, these definitions are the foundation you need. For a deeper look at how data flows across the internet, see our article how the internet actually moves data.
API
Application Programming Interface — a set of rules that lets different software applications communicate and share data with each other. Most apps you use rely on multiple APIs running quietly in the background.
Bandwidth
The maximum capacity of a network connection to carry data, usually measured in megabits per second (Mbps). More bandwidth generally supports more simultaneous users or higher-quality streaming.
Cache
A temporary storage location where a browser or app saves copies of data it has recently accessed. This allows faster load times on repeat visits without downloading the same content again.
DNS
Domain Name System — the internet's address book. It translates human-readable website addresses (like example.com) into numerical IP addresses that computers use to locate servers.
Encryption
The process of converting readable data into a coded format that can only be decoded with the correct key. Encryption protects data in transit and in storage from unauthorized access.
Firmware
Low-level software embedded directly into a hardware device that controls its core functions. Firmware updates are delivered by manufacturers to fix bugs or add features at the hardware level.
Latency
The time delay — measured in milliseconds — between sending a request and receiving a response over a network. Low latency is especially important for video calls, gaming, and real-time applications.
Operating System (OS)
The foundational software that manages a device's hardware resources and provides the environment in which other applications run. Common examples include Windows, macOS, Android, and iOS.
Cloud Storage
A service that stores files on remote servers maintained by a third party, accessible over the internet. Your files are not stored locally on your device but retrieved whenever you need them.
IP Address
A unique numerical label assigned to every device connected to a network. IP addresses allow devices to find and communicate with each other across the internet.
Core Terms: Networks, Data, and Connectivity
These are the words you're most likely to see when dealing with internet connections, streaming, or device setup.
| Typical home broadband bandwidth | 100–500 Mbps (Federal Communications Commission broadband benchmarks) |
| What 'https' signals | Encrypted connection |
| Latency considered low for video calls | Under 150 ms (ITU-T G.114 recommendation) |
| Cache clearing effect | Slower first reload, cleared stored data |
| Firmware update delivery | Over-the-air (OTA) or via USB |
Bandwidth describes the maximum amount of data your connection can carry at once — often measured in megabits per second (Mbps). Higher bandwidth generally means faster downloads and smoother streaming. It's worth knowing that bandwidth and speed are related but not identical: bandwidth is the lane width, speed is how fast traffic moves. For a detailed breakdown of these units, understanding bits, bytes, and bandwidth is worth reading alongside this guide.
A cache (pronounced "cash") is a small store of temporary data that your browser or app saves locally so it can load content faster on repeat visits. When a site loads slowly after you clear your browser history, the cache is often what you cleared. Latency — sometimes called ping — is the time delay between sending a request and receiving a response. High latency is why video calls sometimes feel slightly out of sync even on fast connections. See also: wired vs. wireless internet for how connection type affects both bandwidth and latency.
DNS (Domain Name System) works like a phone book for the internet, translating the web addresses you type into numerical IP addresses that servers understand. How IP addresses and DNS work together is covered in depth in a companion article.
Software Terms: APIs, Firmware, and the Rest
These terms describe how software is built, maintained, and connected — and they come up constantly in tech news and product updates.
An API (Application Programming Interface) is a set of rules that lets two pieces of software talk to each other. When a weather app shows a live forecast, it's using an API to pull data from a weather service. APIs are the connective tissue of the modern internet, enabling apps to share data without sharing their underlying code.
Firmware is a type of software permanently embedded in a hardware device — your router, smart TV, or wireless earbuds all run firmware. Unlike a regular app you install and delete, firmware is tied to the device's core operation. When a manufacturer pushes a firmware update, they're patching or improving the low-level instructions that run the hardware itself.
An operating system (OS) is the foundational software that manages a device's hardware and lets other applications run. Windows, macOS, Android, and iOS are all operating systems. The OS handles memory, file storage, and the interface you interact with. Understanding how apps sit on top of an OS is clarified further in the difference between an app, a program, and a browser extension.
Encryption converts readable data into a scrambled format that only authorized parties can decode. When a website URL begins with https, it means your connection is encrypted. Cloud storage refers to files saved on remote servers you access over the internet, rather than on your local device. What the cloud actually is explains where those files physically live and who controls the servers.
These Definitions Are Starting Points
Tech terminology evolves quickly, and many of these terms have nuances that vary by context. The definitions here are intentionally simplified for a general audience. As you encounter these words in specific products or news stories, the surrounding context will often add important detail.
For device-specific vocabulary — the kind found on spec sheets — the consumer electronics glossary and the smartphone glossary cover hardware-level terms in detail. If you're also building vocabulary in other areas, the same plain-language approach applies to investing terminology.