Years ago for my students, I indexed the simplest YouTube openings videos aimed at post-beginners who were ready to be introduced to specific openings.  And by ready, I mean they were ready in skill level (drilled in opening general principles, adequate and improving in tactics and endgames), and ready in attitude (not being force fed, but hungry to learn!) 

Most of these are from Kevin at The Chess Website, but several are from other sources also.  I've copied and pasted the content below, but my original page has better formatting.

I haven't updated it in awhile, so there may be dead links.  If you can recommend other quality free opening introduction videos, feel free to link to them in the comments.

1.e4 e5 -- 1.e4 other -- 1.d4 d5 -- 1.d4 other -- Flank Openings

Welcome to the Openings Explorer!

Online videos are an effective way to learn a new opening. It's like having a private lesson with a chess coach. This page is intended for chess players who are progressing beyond novice phase (rated over 1200), who know the general opening principles, and who are ready to enjoy the process of trying out new opening repertoires. Have a blast!

I've done a lot of screening and filtering so you won't have to. IMHO, these are the best free videos on the web for introducing chess novices to a new opening. Watch the video, and then try it out! Try out several! Some ideas on how to use this page to maximum effect:

Two handy tools to use when watching: the "Pause" button, and the "Enlarge Screen" button.

Feel free to take notes. If you'd like to read and/or print out a useful synopsis of an opening, go to Wikipedia and type in the name of the opening.

Double King Pawn Openings: 1 e4 e5

King's Gambit pt1 pt2 1 e4 e5 2 f4

King's Gambit: Falkbeer Counter-Gambit 1 e4 e5 2 f4 d5

Vienna Game and Gambit 1 e4 e5 2 Nc3

Center Game 1 e4 e5 2 d4

Danish Gambit (or Danish Gambit by jrobi) 1 e4 e5 2 d4 exd4 3 c3

Urusov Gambit pt1 pt2 pt3 1 e4 e5 2 Bc4 Nf6 3 d4

Boden's Gambit 1 e4 e5 2 Bc4 Nf6 3 Nf3

Latvian Gambit 1 e4 e5 2 Nf3 f5

Petroff Defense 1 e4 e5 2 Nf3 Nf6

Philidor Defense pt1 pt2 1 e4 e5 2 Nf3 d6

Ponziani Opening (also Ponziani Opening in depth) 1 e4 e5 2 Nf3 Nc6 3 c3

Four Knights' Game: Halloween Gambit 1 e4 e5 2 Nf3 Nc6 3 Nc3 Nf6 4 Nxe5

Four Knights' Game: The Fork Trick 1 e4 e5 2 Nf3 Nc6 3 Nc3 Nf6 4 Bc4

Scotch Opening 1 e4 e5 2 Nf3 Nc6 3 d4

Scotch Gambit pt1 pt2 pt3 pt4 1 e4 e5 2 Nf3 Nc6 3 d4 exd4 4 Bc4

Ruy Lopez 1 e4 e5 2 Nf3 Nc6 3 Bb5

Guioco Piano 1 e4 e5 2 Nf3 Nc6 3 Bc4 Bc5

Evans Gambit pt1 pt2 (or Evans Gambit by jrobi) 1 e4 e5 2 Nf3 Nc6 3 Bc4 Bc5 4 b4

Two Knights Defense: Fried Liver Attack 1 e4 e5 2 Nf3 Nc6 3 Bc4 Nf6 4 Ng5 d5 5 exd5 Nxd5 6 Nxf7

Two Knights Defense: Lolli Attack 1 e4 e5 2 Nf3 Nc6 3 Bc4 Nf6 4 Ng5 d5 5 exd5 Nxd5 6 d4

Two Knights Defense: Ulvestad Counter Attack 1 e4 e5 2 Nf3 Nc6 3 Bc4 Nf6 4 Ng5 d5 5 exd5 b5

Two Knights Defense: Traxler Counter Attack 1 e4 e5 2 Nf3 Nc6 3 Bc4 Nf6 4 Ng5 Bc5

Two Knights Defense: Max Lange Attack pt1 pt2 pt3 pt4 1 e4 e5 2 Nf3 Nc6 3 Bc4 Nf6 4 d4

Single King Pawn Openings: 1 e4 other

Sicilian Defense 1 e4 c5

Sicilian Defense: Dragon Variation 1 e4 c5 2 Nf3 g6

Sicilian Defense: Smith Morra Gambit pt1 pt2 pt3 pt4 1 e4 c5 2 d4 cxd4 3 c3

French Defense pt1 pt2 1 e4 e6 2 d4 d5

Caro-Kann Defense 1 e4 c6 2 d4 d5

Scandinavian Defense (or Scandinavian Defense by jrobi) 1 e4 d5

Alekhine's Defense (or Alekhine's Defense by jrobi) 1 e4 Nf6

Pirc Defense 1 e4 d6 2 d4 Nf6 3 Nc3 g6

Pribyl (Czech) Defense 1 e4 d6 2 d4 Nf6 3 Nc3 c6

Modern Defense pt1 pt2 pt3 pt4 pt5 1 e4 g6

Double Queen Pawn Openings: 1 d4 d5

Queen's Gambit 1 d4 d5 2 c4

Queen's Gambit Accepted 1 d4 d5 2 c4 dxc4

Queen's Gambit: Tarrasch Defense 1 d4 d5 2 c4 e6 3 Nc3 c5

Albin Counter Gambit 1 d4 d5 2 c4 e5

Slav Defense 1 d4 d5 2 c4 c6

Semi-Slav Defense 1 d4 d5 2 c4 e6 3 Nc3 Nf6 4 Nf3 c6

London System pt1 pt2 pt3 pt4 1 d4 d5 2 Bf4

Colle-Zukertort System 1 d4 2 Nf3 3 e3 4 Bd3 5 O-O 6 b3

Veresov Attack 1 d4 d5 2 Nc3 Nf6 3 Bg5

Queen Bishop's Attack 1 d4 d5 2 Bg5

Blackmar-Diemer Gambit 1 d4 d5 2 e4

Blackmar-Diemer Gambit: Halosar Trap 1 d4 d5 2 e4 dxd4 3 f3 exf3 4 Qxf3

Single Queen Pawn Openings: 1 d4 other

Nimzo-Indian Defense 1 d4 Nf6 2 c4 e6 3 Nc3 Bb4

Queen's Indian Defense 1 d4 Nf6 2 c4 e6 3 Nf3 b6

Bogo-Indian Defense 1 d4 Nf6 2 c4 e6 3 Nf3 Bb4+

King's Indian Defense 1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 e4

Grunfeld Defense 1 d4 Nf6 2 c4 g6 3 Nc3 d5

Benoni Defense (or Benoni Defense by jrobi) 1 d4 Nf6 2 c4 c5

Benko Gambit 1 d4 Nf6 2 c4 c5 3 d5 b5

Budapest Gambit 1 d4 Nf6 2 c4 e5

Dutch Defense 1 d4 f5

Dutch Defense: Stonewall 1 d4 f5 2 g3 Nf6 3 Bg2 e6 4 Nf3 d5

Flank Openings

English Opening 1 c4

English Opening: Botvinnik System 1 c4 2 g3 3 Bg2 4 Nc3 5 e4

Reti Opening (or Reti Opening by jrobi) 1 Nf3

Bird's Opening 1 f4

Orangutang pt1 pt2 pt3 pt4 1 b4

King's Indian Attack 1 Nf3 2 g3 3 Bg2 4 0-0 5 d3 6 e4

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