Raspberry Pi was developed by the UK-registered "Raspberry Pi Charity Foundation", with Eben Upton as the project leader. In March 2012, Eben Upton of Cambridge University in the UK officially launched the world's smallest desktop computer, also known as a card-type computer. It is only the size of a credit card, but has all the basic functions of a computer. This is the Raspberry Pi computer board. It is an ARM-based microcomputer motherboard, with SD/MicroSD card as the memory hard disk. There are 1/2/4 USB ports and a 10/100 Ethernet interface around the card motherboard (Type A has no network port), which can be connected to the keyboard, mouse and network cable. It also has a TV output interface for video analog signals and an HDMI high-definition video output interface. All of the above components are integrated on a motherboard that is only slightly larger than a credit card. It has all the basic functions of a PC. Just connect a TV and keyboard to perform many functions such as spreadsheets, word processing, playing games, and playing high-definition videos. Raspberry Pi B model only provides a computer board, without memory, power supply, keyboard, chassis or connection.