AVR is a family of microcontrollers.

Compile and upload with:

avr-gcc -mmcu=atmega328p -Wall -Os -o blink.elf blink.c
avrdude -p m328p -c usbasp -e -U flash:w:blink.elf
Image: A schematic showing what some of the individual pins of a 10-pin KANDA connector mean when connected to a USBasp and a Bus Pirate, for the purposes of programming a microcontroller and reading its UART output respectively.

Outputs of the KANDA connector on a USBasp and a Bus Pirate.