Study the gear selector A standard automatic gear selector has the basic four markings:
P: Parking. Select P when you park your car.
R: Reverse. Select R when you want to reverse the car.
N: Neutral. Select N when you want to push the car or tow it.
D: Drive. Select D to drive the car -
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L is low gear (1st),
S is 2nd gear -- both of these are just for limiting the gears in particular situations such as poor road conditions where you don't want the car automatically going into higher gears without your consent. Snowy conditions or towing would be the typical uses.