Aircrack-ng is a complete suite of tools to assess WiFi network security. It focuses on different areas of WiFi security which include, monitoring; packet capture and export of data to text files for further processing by third party tools. Attacking; replay attacks, deauthentication, fake access points and others via packet injection. Testing; checking WiFi cards and driver capabilities (capture and injection). Cracking; WEP and WPA PSK (WPA 1 and 2).
All tools are command line which allows for heavy scripting. A lot of GUIs have taken advantage of this feature. It works primarily Linux but also Windows, OS X, FreeBSD, OpenBSD, NetBSD, as well as Solaris and even eComStation 2.