Create an Etherchannel link

Catalyst WS-C3560X-24T-L  switch EtherChannel provides fault-tolerant high-speed links between switches, routers, and servers. You can use it to increase the bandwidth between the wiring closets and the data center, and you can deploy it anywhere in the network where bottlenecks are likely to occur. EtherChannel provides automatic recovery for the loss of a link by redistributing the load across the remaining links. If a link fails, EtherChannel redirects traffic from the failed link to the remaining links in the channel without intervention.

 I would like to create an etherchannel link between two cisco 3560 switches.

My question is: do all ports involved (4 in this case 2 on each switch) need to be the same number channel? or does the pair on one switch need to be a different channel from the  pair on the other switch.

Probably identifiable number on both sides will make maintenance easier, but technically it does not negotiate any channel name on the wire.

Configuring Layer 3 EtherChannels section of Configuring EtherChannel (Catalyst WS-C3560X-24T-S switch)