How do I know which engine air filter I need?

You can find out which air filter is compatible with your car by checking your vehicle's owner's manual. Or, if you know the exact make and model of your car, you can find compatibility information in individual product descriptions.

What are the basic types of air filters that are available?

Your car comes from the factory with paper air filters. They are disposable and are meant to be replaced. Stock replacement air filters are what will replace the paper filter. They are designed to fit most cars universally and are often reusable and washable. Reusable air filters can be made from cotton gauze or foam. Antique cars might take oil bath air filters, but you won't find them in modern cars.

What is the difference between air intake filters and engine air filters?

Air intake filters are shaped like a tube and are used in sports cars and trucks. They are designed to improve the vehicle's horsepower. Regular engine air filters are rectangular and are found in almost all vehicles.