Many hardware and software tools are available for Microchip megaAVR microcontrollers—both from Microchip and from third parties such as IAR Systems, ImageCraft, Codevision, Arduino and many others. Microchip offers kits ranging from the smaller Xplained kits and debuggers like the AVR Dragon to full-blown debuggers like the AVR ONE! as well as standard development kits like the STK500 known to many designers and hobbyists. The Microchip STK500 kit has sold more than 100,000 units, making it the most successful development kit in Microchip history. This kit is still available, but it is recommended to use the STK600, which offers support for all Microchip Flash-based Microchip AVR microcontrollers as well as USB connectivity to Microchip AVR Studio. AVR Studio is a free integrated development environment that can be downloaded from atmel.com. It includes a GCC C-compiler, an editor, a simulator and interfaces to all Microchip hardware tools and programmers. Microchip provides everything one needs to kick start a design, and to develop and debug it.