An automatic transmission is any transmission that doesn’t require the driver to shift gears.
There are more types of automatic transmissions than ever before, including conventional torque-converter step-gear automatics, dual-clutch automatics (sometimes called automated manuals), continuously variable automatic transmissions and hybrids. Although different in design, their performance can be remarkably alike to the casual driver. Though manual shifting (with paddle shifters) is now a common feature, the automatic functionality and lack of a third pedal mean that a car is an automatic.
Over the years, automatic transmissions have been gaining gears but losing dipsticks. Current models reach as high as nine speeds, and a dipstick for checking the transmission fluid has become rare. Many automatic transmissions are sealed or can be checked only by a mechanic. Always refer to your car’s owner’s manual for the proper service intervals.