Basic and advanced use of oclHashcat (Hashcat) for hacking WPA/WPA2 passwords from the Handshake General information about oclHashcat (HASHCAT)
Hashcat Options
Hashcat comes in two versions:

• Hashcat – Password recovery tool using the central processor
• Oclhashcat – GPU-using tool

Many of the algorithms supported by Hashcat can be hacked in a shorter time when using the well-documented capabilities of the GPU. For this purpose the program oclHashcat is intended, at its use the considerable increase in such algorithms as MD5, SHA1 and others is reached. However, not all algorithms can be accelerated using the GPU. Bcrypt is a good example of this. Because of factors such as branching of data dependencies, serialization and memory (only some are mentioned), oclHashcat is not a comprehensive substitute for Hashcat.