Chevrolet: Problems with Alternator or Battery probably..., abs light, alternator

Question
I was driving yesterday and I noticed my ABS light came on. I didn't think much of it until I noticed my battery light on and all the lights in my car getting dimmer. Either my battery wont recharge or my alternator isn't working. I'm going to try hooking it up to my sister's car for about 20 minutes to see if the battery can get a decent charge. If so, then it is probably a problem with the alternator. Otherwise, it should be a problem with the battery right? I was also told a fuse might be the problem, that it might've blown to protect the battery or something. If you could help me figure it out i'd appreciate it

Answer
You didn't say what car you own but if its a GM and the dash fuse blows, the alternator won't charge.

Do your lights get brighter if you rev the motor? Do your lights stay dim even while you're driving?

I'd guess alternator because the battery is mostly used for start up and at idle. At driving speed your alternator has more than enough juice to keep you running.

But if your alt has been dying for a while the battery is gonna need to be replaced as well.