CGMiner is the most popular GPU / FPGA / ASIC miner, CGminer is an open source GPU miner written in C and available for multiple platforms such as Windows, Linux and OS X. One of the things that make it extremely popular , is the fact that it is based on the original Cpu Miner code.
CGMiner includes overclocking, monitoring, fan speed control and remote interface capabilities. Its other features include self-discovery of new blocks using a mini-database, binary core loading, multi-GPU support, and support for CPU mining. There are many other characteristics that you can find out here on the official CGminer forum.
Installing and configuring CGMiner
The first step is to install the latest version of the program that is suitable for the operating system from any reliable source, and then the program must be prepared for work and given personal data for mining.