The Teensy is a complete USB-based microcontoller development system, in a very small footprint! All programming is done via the USB port. No special programmer is needed, only a standard “Mini-B” USB cable and a PC or Macintosh with a USB port.
USB can be any type of device
AVR processor, 16 MHz
Single pushbutton programming
Easy to use Teensy Loader application
Free software development tools
Works with Mac OS X, Linux & Windows
Tiny size, perfect for many projects
Available with pins for solderless breadboard
Comes with assembled Teensy board (ATmega32u4 with bootloader preinstalled) and header to allow easy breadboarding. We suggest using AVR-gcc (like WinAVR) with the LUFA library or ‘Teensyduino’ Be sure to check out the multiple resources available at PJRC!