Digital Art Platform?

I'd like to get a digital art app/platform, and I was wondering if anyone has any recommendations :)
Also, since I'm not planning on using deviant art, can I still use lines from there/lines in general? How do lines work?
Any pointers on art (and anything, frankly I've nothing to do with digital art as of yet :P) would be appreciated. 
Thank you, and Merry Christmas! ♥

For free art programs, I hear that Gimp and Fire Alpaca are pretty good and very similar to Photoshop.

As for using dA lines without a dA account, just be sure to read the artist's rules in the descriptions pertaining to usage off-site. Each artist has different rules about off-site usage. You can always just create an account just to ask the artists any questions about it ^^
I also suggest searching tutorials on dA for art pointers. There's tons of good ones on there that have helped me tremendously!

Krita is another good program that's free. It's what I use and I love it.

Thanks! I'll look into them :D

Ahh, I remember the good old days where I first learnt to do digital art ... on GIMP!

It's like Photoshop but a really, ripped-off, lamer, older, rustic .. well, the list goes on, haha. But nevertheless, it taught me how to use PS actually and I find that the very basic/base stuff is pretty much the same. 

The latest release of GIMP is actually /extremely/ close to PS. I recommend giving it a try, most people seem to forget releases past 2.6 exist lol.

I'm in the same boat though! I can't find a platform to post art on anymore, deviantart and tumblr are both dead. I've heard twitter is good but I have yet to try it.

I use Paint Tool SAI! You get a 30 day free trial then its $50 (I believe) one time! It's really simple and easy to get the hang of. DA also has a ton of custom brushes you can buy/download too, so that's really helpful (: