I really don't think there is that much difference between brands if that's what you mean. You should consult your owners manual for the best weight to use in your particular vehicle. I use 10W30 in the summer and 5W30 in the winter.
The brand is probably just a matter of preference, but you need to know the type of motor oil you need. Some oil is better for certain types of cars. Others are better for summer and others are better for winter.
It just says that this oil meets or exceeds car manufacturers standards.
As far as weight, the larger the second number, the thicker the oil. So an oil with a viscosity rating of 20W50 would be very thick; oil rated 5W30 is thin. Thick oil is for summer use, thin oil is for winter use.
Be sure to check your owners manual and use what they suggest.
RoadWarrior, this is helpful as I always just go with whatever the service center says to use, or with whoever is changing my oil. I know it's not smart, but I've never sat down with the auto owner's manual to check oil issues.
I agree 100% with what Roadwarrior said. Here's another helpful bit of information...
There are oils labeled "non detergent." You do not want to put that oil into your car. It's the cheapest kind of oil available, and it's basically for old junkers that don't/won't go over 30 miles per hour. At interstate speeds, this oil will fry your engine. Please, don't put non detergent oil in your car unless you want to completely destroy the engine.