Raspberry Pi 4 Model B (2 GB)

Jargon buster

Plain-language definitions for the technical terms used above.

BLE

BLE stands for Bluetooth Low Energy, a Bluetooth mode designed for low power use and broad compatibility with modern phones and computers. It connects well to battery-powered and mobile devices, including Apple hardware, though it behaves differently from Bluetooth Classic and its serial-style profiles.

dual-band Wi-Fi

Wi-Fi that can use both the 2.4 GHz and 5 GHz radio bands. This matters because 2.4 GHz often reaches farther while 5 GHz can be faster and less crowded, giving more flexibility for wireless projects.

GPIO

General-purpose input/output pins are microcontroller pins you can set in software to read signals, switch devices on and off, or connect to peripherals. The number of GPIO pins matters because it limits how many buttons, LEDs, sensors, and other parts you can wire directly to the board.

HDMI

HDMI is a common digital video and audio connection used by computers, media players, and many displays. If a display kit has HDMI input, it is usually much easier to test with a single-board computer because it can act like a normal monitor.

IoT

Short for Internet of Things, meaning physical devices that connect to networks or the internet to send data or be controlled remotely. It matters if you want projects such as connected sensors, remote controls or classroom data-logging activities.

LPDDR4

A low-power type of RAM commonly used in phones and embedded computers. More LPDDR4 memory lets a board run larger programs, Linux services, or AI models more smoothly.

microSD card

A microSD card is a small removable flash memory card used to store data such as audio, images, logs or program files. Its capacity and formatting (often FAT32 or exFAT) affect how much can be stored and whether the card needs preparing before use.

PoE

Power over Ethernet lets one Ethernet cable carry both network data and electrical power. This is useful when installing a device where running a separate power adaptor would be difficult.

RAM

RAM (random-access memory) is fast, temporary memory a device uses for working data while it is running; in its common volatile form, its contents are lost when power is removed. Some devices offer a mode that applies settings to RAM only, which is handy for testing changes temporarily because they are not stored permanently and disappear at power-off.

USB 2.0

USB 2.0 is a widely used wired standard for carrying both data and power between a device and a computer or other compatible host, with data rates up to 480 Mbps. It indicates the kind of port a device uses and that it should work with most modern and many older computers.

USB-C

USB-C is a small, reversible USB connector that can carry power, data and, on some devices, video over a single cable. The same connector can range from charging only to high-speed data, so the functions a given port actually supports vary.