Look at these sentences:
I walk along the road
The traffic jam along the road
I walk alongside the road
The traffic jam alongside the road
The first sentence means as the same direction as the road (correct me If I'm wrong), Though, I don't know if the second means "the traffic is in a line next to the road" or if the traffic is on top of the road.
And when should I use along and alongside ? (Can you guys please give me examples and tell me all the meanings of each word?)