Why/when to use .concat or the '+' sign

[IT2Be]

I was playing with my HowTo example and found that string.concat is not (always) needed.

binding two or more strings can be done like:

a = a.concat(b,c) or

a = a + b + c

When or why should we use one or the other?

Thanks

[Jan_Blok]

There is no difference