Raspberry Pi

Raspberry Pi 
  • is a single-board computer
  • has almost everything a board of a desktop computer has
  • has these popular models: Pi 3 Model B, Pi 2 Model B, Pi Zero
  • is widely used in IoT projects for building the "things"
  • can be used in learning, prototyping, and product development

Raspberry Pi CM3 (Compute Module 3)
  • has industrial strength
  • uses BCM2837 processor at up to 1.2GHz
  • has 1 GByte of RAM
  • has 4 Gbytes of on module eMMC flash
  • is priced at US$30
  • has a light version (US$25) which only provides interface pins for eMMC flash or SD card 

Raspberry Pi Zero W:
  • is Raspberry Pi Zero plus WiFi and Bluetooth
  • Priced at $10

Key Specs of Raspberry Pi 2 Model B 
  • Quad-core ARM Cortex A7 with ARMv7-A Instruction Set; frequency 900MHz
  • Broadcom VideoCore IV GPU; frequency 250 MHz
  • 1 GB SDRAM (LPDDR2-900)
  • 10/100 Ethernet
  • No wireless support
  • 4 USB ports
  • micro-SD card
  • Camera interface
  • HDMI/composite video
  • HDMI/headphone audio
  • 40 GPIO Pins (can be used as UART, I2C, SPI)
  • Power: 800 mA, 4.0 W
  • Dimension: 86.9mm x 58.5mm x 19.1mm (3.4" x 2.3" x 0.8")
  • Weight: 41.2g (1.5oz)
  • Priced at US$35

Key Specs of Raspberry Pi 3 Model B
  • 1 GB SDRAM (LPDDR2-900)
  • 10/100 Ethernet
  • 802.11n, Bluetooth 4.0
  • 4 USB ports
  • micro-SD card
  • Camera interface
  • HDMI/composite video
  • HDMI/headphone audio
  • 40 GPIO Pins (can be used as UART, I2C, SPI)
  • Power: 800 mA, 4.0 W
  • Dimension: 86.9mm x 58.5mm x 19.1mm (3.4" x 2.3" x 0.8")
  • Weight: 41.2g (1.5oz)
  • Priced at US$35

Key Specs of Raspberry Pi Zero:
  • Broadcom VideoCore IV GPU; frequency 250 MHz
  • 12 MB SDRAM
  • No Ethernet
  • No wireless
  • micro-SD card
  • HDMI/Composite video
  • HDMI audio
  • 40 GPIO Pins
  • 1 Micro-USB
  • Power: 160 mA, 0.8 W
  • 65 mm × 30 mm × 5 mm (2.56 in × 1.18 in × 0.20 in)
  • Weight: 9g (0.32 oz)
  • Priced at US$5
  • Designed to be customized for specific applications

OS of Raspberry Pi
  • Raspbian is the "official" OS for Raspberry Pi
  • Raspbian is a UNIX-like OS
  • Raspbian is based on Debian
  • Raspbian uses PIXEL
  • PIXEL stands for Pi Improved Xwindows Environment Lightweight
  • Raspberry Pi can also use the Windows IoT Core OS