"I want to buy Catalyst 2960-X series switches like WS-C2960X-24PS-L,WS-C2960X-24PD-L, buy I'm not very well know about c2960x series. Can someone help me ?"--from yahoo answer.
All Catalyst 2960-X Series Switches use a single Universal Cisco IOS Software Image for all SKUs.Cisco Catalyst 2960-X Family of Switches are available with the LAN Base and LAN Lite feature sets.


WS-C2960X-24PS-L Overview
Catalyst 2960-X 24 GigE PoE 370W, 4 x 1G SFP, LAN Base Switch


WS-C2960X-24PD-L Overview
Catalyst 2960-X 24 GigE PoE 370W, 2 x 10G SFP+, LAN Base Switch