What is the difference between a Truck and a SUV?

I currently drive an SUV but I am considering purchasing a Truck the next time I purchase a new automobile.
What is the difference between a Truck and a SUV, and which vehicle is better to drive?

Gas cost to drive to mexico in a V8 SUV?

How much do you reckon would it cost me in gasoline to drive my V8 SUV out to Mexico?
I’m planning a trip soon and I would like to estimate the cost so that I know about how much I will need to set aside for gas.

What is the difference between a 4WD SUV and a 4×4?

Is there any difference? I called a rental car to rent a 4WD SUV and they said,"Do you mean a 4×4?" I thought they were the same thing.
Also, bonus points to someone who can tell me what the numbers signify. I know one of them tells you if it is a [...]

Cheap, reliable 4WD SUV suggestion?

What is a good cheap reliable second-hand 4WD SUV to get around in?

What is a crossover vehicle?

How do you define a crossover vehicle?