There is no concept of "fast switch" in cisco lan switches. If you are talking about store and forward or cut-through switch, most of the CATOS switches are store and forward switches.
For example Catalyst 6500 with sup2/msfc2 uses CEF mechanism for better performace where sup1/msfcx uses MLS mechanism to achieve good performance.
I suggest that you read up the lan-swithes documentation online
http://www.cisco.com/univercd/home/home.htm
The above link has product documentation and description of various swithes.