In every 2 weeks a new topic about caps is started and everytime it is all explained.
Some research before asking a same question would be nice.....
Edit: OK, because I can be nice....
A simple search and some reding within a minute some topics about caps:
https://www.rctech.net/forum/radio-e...or-enough.html
https://www.rctech.net/forum/radio-e...apacitors.html
https://www.rctech.net/forum/radio-e...capacitor.html