Firstly the difference between a highway and a normal road is that there are no red lights or stop signs on highways. That being said cars drive faster. But you knew all that.
Highways come in 3 varieties for me, the 2-lanes, 3-lanes and 4+- lanes. I shall now attempt to use my ascii skills to explain the essentials about each lane.
2-Lane Highways
These highways are usually located in rural areas or places that don't usually get a lot of traffic.
Right-hand lane <-- {car} <-- [truck]
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Left-hand lane <--- {car} <---- {car} <--- {car}
In Right-hand lane (90-115 km/h)
- Trucks: they can't drive too fast, they run on a different speed limit and it's generally more dangerous if a giant truck crashes. Momentum and what not.
- Cars getting on and off the highway
- Cars that follow the speed limit
- Cars that're are lazy and want to just cruise by
- Cars that have a hard time accelerating
In Left-hand lane (115+ km/h)
- Cars attempting to get to their destination faster
- Cars that are trying to overtake slower cars in right-hand lane
- Extremely reckless drivers
3-Lane Highways
These highways are usually still found in rural or less crowded areas, but generally come from or are going to a major city.
Right-hand lane <-- [truck] <- {car}
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Middle lane <-- {car} <-- {car} <-- [truck]
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Left-hand lane <--- {car} <------ {car}
Right-hand Lane (90-110 km/h)
- Trucks
- Cars getting on and off of highway
- Cars driving religious by the speed limit
Middle Lane (110-120 km/h)
- Cars just cruising by
- Some trucks
- Cars trying to over take slow vehicles in the right-hand lane
Left-hand Lane (120+ km/h)
- Cars trying to over take a relatively slow care in the middle lane
- Insane speeding drivers
Often I find that the right-hand lane can turn into a faster lane because a lazy cruising driver in the middle lane's slowing people down and people are more wary of being in the left-hand lane where the insane speeders drive. In fact these categories are just a general thing, once the left-hand lane turned into the slowest lane for me.
I'm not going to bother commenting on highways with more than 3 lanes because there, anything goes. And there's that added complexity of the High Occupancy Lane sometimes for major highways.
All in all, I think this road trip was extremely educational.