DriverSide's Car Dictionary has the most comprehensive definitions of automotive terms. This auto glossary can help you decipher what your mechanic is fixing and what the purpose or function of the particular auto part or accessory is for. We have taken the mystery out of automotive service jargon, so that you don't have to.
The two metal posts which protrude off the top or side is the battery. One terminal is positive, the other negative. These should be clean to allow the battery to function properly, though care must be taken when cleaning the "crust" from the posts, as it is usually acidic and dangerous.