All 400 series highways are marked Freeway, as they are limited access freeways. Other limited-access highways may also be marked Freeway.
Provincial highways that collect traffic from the minor highways, Examples include the 174 east of Ottawa/Orleans, the 17, the 138, 38 the 7 in eastern Ontario.
County roads may be marked Minor Highway if they have higher speed limits than most main roads around them. Not all county roads should be designated "Minor Highway" -- grid roads should be addressed like Alberta's Range / Township Roads.
Roads in cities
Consider copying information here from Nagamasa's user page.