It happened all of a sudden. One day, it was working perfectly, and the next, my MacBookPro couldn't turn on without being plugged to a power source. Unfortunately, I was literally days away from a work trip that was going to take me through many countries, and many hours on airplanes. Not being juiced wasn't an option.
Thankfully, even in disarray, Apple pulls through. Click on the battery icon in your status bar and follow the steps:
IF YOU ENDED IN "SERVICE"
If you ended in Service, you should first check your Coverage Status. This will tell you right away whether or not your computer is still covered by Warranty or by the Apple Care Plan. If it is, and if your battery was not damaged by you, then Apple will probably cover the replacement (this depends on your personal warranty).
Whether you are covered or not, click on the "Set Up a Repair" tab, and schedule an appointment at an Apple Retail Store. If you don't you run the risk of waiting for long periods of time. I haven't scheduled many appointments, but when I have, they've been rather timely.
IF YOU ENDED IN "POWER"
The first step is to look at your Cycle Count & Condition.
If the condition is "Good" or "Normal", then you should be fine. If your Cycle count is close to or above 500, then you may have begun depleting the battery, and it will give out sooner or later. It is normal for a battery to not charge as much as it used to.
IF NEITHER APPLIED TO YOU
Then you may have a process or program hogging a lot of resources. One way to check this is to go into your Applications/Utilities/Activity Monitor and try to find the culprit. Using maximum brightness will also affect the performance of your battery
FOR THE DO IT AT HOMERS
A SPECIAL THANK YOU