How to choose algorithm ?

Question

Sometimes there's different algorithms that gives the same result.
How do you choose witch one to use ?

Ex:
sorting algorithms (Tim sort, bubble sort...)
swapping variables(
a,b = b,a
or
a = a+b
b= a-b
a= a-b)
...

Answer 1

You need to use the most adapted algorithm for your problem : the one which require the less steps or the fastest one