[seabass-labrax]

There are co-operatives in manufacturing which would need their staff to be security-cleared in order to win government contacts (such as assembling weapons). Perhaps this is what parent is referring to. Co-ops aren't just for groceries :)

[xav0989]

In the Canadian university lingo, co-op refers to a (usually paid) internship that you complete as part of your degree. You usually have a couple co-op terms/semesters along with your traditional terms. For example, you may start your degree with two semesters of classes, then a semester of co-op, then one of classes, then another two co-ops, more classes, etc. until you complete the degree requirements. Degrees with a co-op requirement usually will make mention of it (e.g. Software Engineering with co-op).

[seabass-labrax]

Oh, that's really interesting. We have them in the UK too, but they're called placements rather than co-ops.