Infotype Operation

Hi,

Can someone explain me following Infotype operation's, with an example please and also, how we should decide which operation for an Infotype will suit the best to the client.

Create INS

Copy COP

Change MOD

Delimit LIS9

Create operation for actions INSS

Please do not copy paste R/3 defined definitions here,I have already gone through it and I'm looking for further explanation.

Thanks,

Tk