trap vector versus branching

[daf12]

What is the difference between a trap instruction and branching?
I read that a trap vector is much like an interrupt and when a trap instruction happens, program jumps to a subroutine.
Why can't branching be used? What is the difference between trap vector and branching? I thought that both perform the same instruction. thanks

 

[strettonman]

A trap is an interrupt which occurs as a result of some action taken by the program - such as setting the single step flag, executing an INTO instruction, or issuing a break point interrupt. Unless you are doing something relatively specialised, such as writing a degugger, you seldom if ever need to worry about them.