which layer to use for developement of an Add-on?

Hi All,

As we are going to develope Add-on, which layer should we use for our development!!?

As there are var,bus,usr layer is available!

i searched for this, i think we have 2 option VAR or BUS!

but not excetlly know which!!? any one have idea on this LAYERS!!?

It shud be BUS layer



hi narayan,

Thank you for replay,

why to use BUS? any specific reason!?