Toyota Repair: start up problem with 98 Toyota Tacoma, 4 cylinder, alternator problem, alternator output

Question
Today I was driving down the highway when the truck started running rough and then stopped running altogether and I had to pull it over to the side of the road.  It would not start back up, but tried to turn over.  Could this be a fuel problem?  Thanks.

Answer
Possibly an alternator problem, was the engine able to be jump started with a good battery?
If that's the case have the alternator output checked.
It could be a fuel problem ,if the starting and charging system are ok have the fuel pressure tested. It could be a bad fuel pump.