Hello, all! I was planning on using this forum space to post links to online resources that I have found helpful in my personal chess study. If you have links to share, feel free to leave them here :)
On youtube I highly recommend the following for a start:
https://www.youtube.com/user/STLChessClub
https://www.youtube.com/user/wwwChesscom
https://www.youtube.com/user/Chessexplained
And for opening-specific research I recommend the following databases:
Chessgames.com
Chess.com (under "Learn")
Chesstempo.com (under "Chess Database")
For free tactics training:
Chesstempo.com (you can make an account to track your progress and get harder puzzles, but even if you just do tactics as a guest you get very interesting, albeit steady- difficulty positions to solve).
http://chess.emrald.net/ This one is also ok, but the interface is less user-friendly, I have found.
And, of course, chess.com, though you get only a limited number of puzzles per day unless you have a paid membership (which I used to have). Still, a good tactics trainer on this site.