Please talk me through Photoshop 'Curves'

[gramps]

I'm using CS6 and I get 'Levels' but I've never got a handle on 'Curves' ... I sort of get the general idea of what it does but how, why and detail of it are lost on me.
Anyone put me out of my misery?

 

[Gr8Shot]

this should help

 

[Gr8Shot]

And a video from Adobe

 

[troutfisher]

Have a look here http://tv.adobe.com/watch/understanding-adobe-photoshop-cs6/working-with-curves/ for starters and Lynda.com have some good tutorials as well

 

[gramps]

Ta

 

[swanseamale47]

Another tip if you find the grid or the curves box too large alt+click on the grid to change it from quarter tone to 10% grids.