What is an f-stop?

I found a nice explanation what the ratio and how it is configured:

http://en.wikipedia.org/wiki/F-number



Other helpful sites to check out:

- For post processing:

http://www.lightroomkillertips.com/ - great lightroom tips, tricks, tutorials and freebies

http://coffeeteaphotography.blogspot.com/ - free actions, presets, tutorials, textures and more

http://www.gettotallyrad.com/ - awesome actions
http://www.sheyerosemeyerphotography.com/blog/eye-candy/ - more awesome actions



- Photographer Community

http://shuttersisters.com/ - great writting and inspiration

http://julescafe.com/ - learn, grow and share with others

http://www.twiplog.com/episodes/ - weekly pod cast about photography and gear
http://www.thebschoolblog.com/ - Becker (a socal photographer's) blog



- Photo Stuff

http://photojojo.com/

http://www.dpreview.com/ - great place to learn about cameras