Think about your MP3 player, TV remote, and your favorite Digilent Micro-controller board. All these have firmware installed onto them. Firmware is loaded onto an embedded systems non-volatile memory. Firmware is background code that you never see, but keeps everything running smoothly. Sometimes you have to flash your board, which is uploading new code onto your board directly. This will mostly happen when you’ve written custom firmware for your board, then decide to go back to the original firmware for the board.
You can use the chipKIT PGM Programmer/Debugger to upload new firmware onto a chipKIT board. All you’ll need is chipKIT board (perhaps the WF32), the MPLAB X IDE, the bootloader file, a USB A to mini-B cable, and a 6-pin right angle male header.