Nope, you take 2 electives in first year engineering:
http://registrar.mcmaster.ca /CALEN...13/pg1197.html
6 units means 2 courses, because 1 course is usually (at least in first year engineering) 3 units...programming is a 4 unit course (1d04).
A lot of first year engineering students take Econ 1b03&1bb3 (micro and macro econ). You should really take an elective based on what you like.
Here is a list of electives (remember to choose what interests you, so it can be an average booster!):
http://www.eng.mcmaster.ca/documents/electives.pdf
Good luck !