My car cranks but won't start? Help?!

My car has been stalling lately. It's not my battery. Sometimes it would happen when I was still. Then it started happening when I was driving and became a little scary. What always happened was that I would wait a few minutes and it would start up.
Today, it didn't turn on at all and just cranks. What could my problem be? I just changed an air filter in the front.
Added (1). It's a 2000 Honda.

@ Ellen, yes the lights come on.
The meter that your talking about, is it the handheld one that can tell any issues with the vehicle? Cuz my friend can probably get that to check my car, since it still won't start.

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