Parabolic SAR

Can anyone please give me some details or point me to a tutorial of how this is suppose to work? What is based on? What is the significance of Step and Maximum parameters in this indicator?

Usual settings are 0.02 but what's the impact if I increase/decrease them?

Thanks in advance for your help.

You can easily get this answer by doing a web search. You will get your answer a lot faster and in more detail. You will also find your answer by doing a search on this forums archives.