<P> Several generations of Raspberry Pis have been released . All models feature a Broadcom system on a chip (SoC) with an integrated ARM - compatible central processing unit (CPU) and on - chip graphics processing unit (GPU). </P> <P> Processor speed ranges from 700 MHz to 1.4 GHz for the Pi 3 Model B+; on - board memory ranges from 256 MB to 1 GB RAM . Secure Digital (SD) cards are used to store the operating system and program memory in either SDHC or MicroSDHC sizes . The boards have one to four USB ports . For video output, HDMI and composite video are supported, with a standard 3.5 mm phono jack for audio output . Lower - level output is provided by a number of GPIO pins, which support common protocols like I2C . The B - models have an 8P8C Ethernet port and the Pi 3 and Pi Zero W have on - board Wi - Fi 802.11 n and Bluetooth . Prices range from US $5 to $35 . </P> <P> The first generation (Raspberry Pi 1 Model B) was released in February 2012, followed by the simpler and cheaper Model A . In 2014, the Foundation released a board with an improved design, Raspberry Pi 1 Model B+ . These boards are approximately credit - card sized and represent the standard mainline form - factor . Improved A+ and B+ models were released a year later . A "Compute Module" was released in April 2014 for embedded applications . The Raspberry Pi 2, which added more RAM, was released in February 2015 . </P> <P> A Raspberry Pi Zero with smaller size and reduced input / output (I / O) and general - purpose input / output (GPIO) capabilities was released in November 2015 for US $5 . By 2017, it became the newest mainline Raspberry Pi . On 28 February 2017, the Raspberry Pi Zero W was launched, a version of the Zero with Wi - Fi and Bluetooth capabilities, for US $10 . On 12 January 2018, the Raspberry Pi Zero WH was launched, the same version of the Zero W with pre-soldered GPIO headers . </P>

When did the first raspberry pi come out