Laptop Battery Plugging in not charging

[kenghtt]

I once saw a post that showed me how to test my battery to see if it was my battery or if it was my charger that was bad.
Does anyone have any idea about this? People say just look at the wire or maybe its overheating....but I need some real concrete tests. Does anyone know how to test a battery to see if its going bad? or a way to test the charger? Sometimes I would have to unplug and plug my charger into my laptop multiple times for it to finally recognize a charge.