Inukshuks

So, as I've been driving along the Trans-Canada, I've noticed a ridiculous amount of inukshuks along the highway. Now, I've been told that inukshuks are supposedly used by native people to mark a path, or a good fishing or hunting site, etc. I'm kinda wondering where these inukshuks came from, who put them there and why. Cause I'm pretty sure that the rocks that line the Trans-Canada are not very good fishing or hunting sights... unless you are hunting moose in the middle of the night with your car. Which thankfully I am not :)

Any insights fellow Trans-Canada travellers??