Suffered a spill? Water, wine, beer, alcohol, tea, coffee, juice, milk - it's a heart-breaking occurrence and can be very costly, especially if you ask the technicians at Apple for a quote. SimplyFixIt work on the basis that it's better to repair the components rather than automatically replace them. In nearly every case we're considerably cheaper than Apple for liquid damaged Macs.
The unholy trinity of a MacBook, a wine glass that still has liquid in it, and a cat, all on the same table.
When water damage has occurred, the liquid will likely make its way to the Logic Board (the main circuit board in the computer) and other components inside. The minerals and salts in the liquid immediately begin to eat away at the metal, silicone that the components are made of. If there is a power source available, such as a battery, which is supplying power to the system (even when the computer is turned off), the electric current will interact with the liquid and accelerate the corrosion process. (This is the case in most MacBook computers since 2010 because the battery is not removable, and is one of the reasons that it's incredibly important to get your MacBook looked at as soon as possible.) This corrosion gets worse over time if not treated, so you may have a computer with just a sticky keyboard today, but next month the corrosion has caused the computer to stop working altogether.