Metasploit

The Metasploit Project is a computer security project that provides information about security vulnerabilities and aids in penetration testing and IDS signature development. The framework is maintained by Rapid7 and the community. Its best-known sub-project is the open source Metasploit Framework, a tool for developing and executing exploit code against a remote target machine. Other important sub-projects include the Opcode Database, shellcode archive and related research. The Metasploit Project is well known for its anti-forensic and evasion tools, some of which are built into the Metasploit Framework.

Installation
Rapid7 recommends using the binary installer for the desired version. The installer comes with a guide that aims to help during the installation process. If someone wants to develop and contribute, there's a guide to set up a development enviroment.

External resources

 * Downloads by version (official) - Metasploit's versions.
 * Metasploit unleashed - Offensive security's Metasploit course.
 * Rapid7 free tools - some free tools from Rapid7
 * Community's documentation - some comunnity's documentation
 * Armitage - Metasploit front-end UI