The RPi is available in two models. Model A and Model B. They are very similar but the cheaper Model A does not include a network port and only provides one USB port.
The Model A was expected to be used more widely in schools due to its lower cost but the lower power consumption may also make it ideal for other projects.
The table below shows the hardware specification of both models :
| Model A | Model B | |
|---|---|---|
 |  | |
| Price | US$25 (GBP £20) | US$35 (GBP £28) |
| System (SoC) | Broadcom BCM2835 (CPU + GPU + SDRAM) | |
| CPU | 700 MHz ARM11 ARM1176JZF-S core | |
| GPU | Broadcom VideoCore IV, OpenGL ES 2.0, OpenVG 1080p30 H.264 high-profile encode/decode | |
| Memory | 256 MB | 512 MB |
| USB 2.0 ports | 1 | 2 |
| Video outputs | Composite video, Composite RCA, HDMI | |
| Audio outputs | 3.5 mm jack, HDMI Audio | |
| Audio inputs | None | |
| Storage | SD/SDHC card slot | |
| Network | None | 10/100 Ethernet RJ45 |
| Low-level peripherals | General Purpose Input/Output (GPIO) pins, Serial Peripheral Interface Bus (SPI), I²C, I²S, Universal asynchronous receiver/transmitter (UART) | |
| Real-time clock | None | |
| Power ratings | 500mA, (2.5 Watt) | 700mA, (3.5 Watt) |
| Power source | 5V via Micro USB connector | |
| Size | 85mm x 56mm (more mechanical details here) | |
The Model B originally shipped with 256MB but this was upgraded so all Model Bs now come with 512MB.