There are good traps and bad traps.

A good trap is a trap you set with a good move

A bad trap is a trap you set with a bad move

If your opponent plays a good move against your bad move, you will have a worse position! So don't play a bad trap, but do learn about them.

Good AND bad traps teach you nice tactics ideas, and remind you to be careful -- especially in the opening! So they are all worth looking at.

Traps

Click [...] to see list or F3 to see the next one

[Event "Elephant trap"]
[Site "Queen's Gambit"]
[Date "2020.05.28"]
[Round "?"]
[White "Good"]
[Black "Traps"]
[Result "*"]
[ECO "D35"]
[PlyCount "18"]

1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. cxd5 exd5 6. Nxd5 $4 Nxd5 $1 7.
Bxd8 Bb4+ 8. Qd2 Bxd2+ 9. Kxd2 Kxd8 *

[Event "Albin Counter-Gambit"]
[Site "Lasker's Trap"]
[Date "2020.05.28"]
[Round "?"]
[White "Good"]
[Black "Traps"]
[Result "*"]
[ECO "D35"]
[PlyCount "16"]

1. d4 d5 2. c4 e5 3. dxe5 d4 4. e3 $6 (4. Nf3 Nc6 5. Nbd2 Bg4 6. a3 Qe7 (6...
Nge7 7. h3 Bxf3 8. Nxf3 Ng6 9. e3 dxe3 10. Bxe3 $16) 7. b4 O-O-O 8. Bb2 $14)
4... Bb4+ 5. Bd2 dxe3 6. Bxb4 $4 exf2+ 7. Ke2 fxg1=N+ $3 8. Rxg1 Bg4+ *

[Event "Monte Carlo"]
[Site "?"]
[Date "1892.01.29"]
[Round "?"]
[White "Tarrasch"]
[Black "Marco"]
[Result "*"]
[ECO "C66"]
[Annotator "DrDave"]
[PlyCount "35"]

{Just for contrast, here's a Good Trap, discovered by Tarrasch. White plays
only good moves, but if Black doesn't choose correctly, White can spring a
trap!} 1. e4 e5 2. Nf3 Nc6 3. Bb5 {The Ruy Lopez. In this line, Black goes for
the most solid and safe moves they can find, hoping their strong point in the
centre will provide shelter...} d6 (3... -- 4. Bxc6 dxc6 5. Nxe5 Qd4) 4. d4 Bd7
5. Nc3 Nf6 6. O-O Be7 7. Re1 {

[#]

So far, so good.} O-O {Black plays one
'safe' move too many! White can win a pawn here, for if Black tries to hit
back and win a pawn back, White wins at least an Exchange. 

[#]

} (7... exd4 $1
$14 {is best here, but because White has been playing good moves on each turn,
White can still claim a small advantage.}) 8. Bxc6 {

[#]

TACTIC: Undermining e5.
} Bxc6 9. dxe5 dxe5 10. Qxd8 Raxd8 ({If} 10... Rfxd8 11. Nxe5 {Black can't win
back the pawn by} Bxe4 12. Nxe4 Nxe4 {because of the same idea:} 13. Nd3 f5 14.
f3 Bc5+ {Here White can just step aside and win a piece} 15. Kf1) 11. Nxe5 {

[#]

TACTIC: Finally getting around to taking the pawn on e5.} Bxe4 {e4 is
outnumbered.} 12. Nxe4 Nxe4 {

[#]

Has Black been clever?} 13. Nd3 {

[#]

TACTIC:
blocking the d-file and discovering an attack down the e-file -- a pin or a
skewer.} (13. Rxe4 {

[#]

TACTIC: back rank mate} Rd1+ 14. Re1 Rxe1#) 13... f5
14. f3 {

[#]

TACTIC: attacking a pinned piece.} Bc5+ 15. Nxc5 $1 {With the
Black Rooks on d8 and f8, there is a different way to win:} ({Sidestepping
here doesn't work so well:} 15. Kf1 Bb6 16. fxe4 fxe4+ 17. Nf4 g5 18. Rxe4 gxf4
19. Ke2 Rde8 $11) 15... Nxc5 16. Bg5 {

[#]

TACTIC: a fork on e7 is threatened.}
Rd5 17. Be7 {'1-0 (17) Tarrasch,S-Marco,G Dresden 1892 EXT 1998 

[Tartakower/du
Mont/Tarrasch/Reti]

'} Re8 {

[#]

Black has fought hard to hang on, but...} 18.
c4 {

[#]

TACTIC: undermining the defence of c5. Tarrasch's clever line is like
a little course in tactics, all by itself. Another notable thing about it:
Tarrasch published this line in a magazine, explaining why Black couldn't
safely castle on move 7, before winning this game against Marco!} *

Bad Traps

Click [...] to see list or F3 to see the next one

[Event "Blackburne's Shilling Gambit"]
[Site "?"]
[Date "2020.05.28"]
[Round "?"]
[White "Bad"]
[Black "Traps"]
[Result "*"]
[ECO "C50"]
[PlyCount "14"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Nd4 $2 4. Nxe5 (4. Nxd4 exd4 5. O-O c6 6. Re1) (4.
c3 Nxf3+ 5. Qxf3 Qf6 6. Qe2) 4... Qg5 5. Nxf7 $4 Qxg2 6. Rf1 Qxe4+ 7. Be2 Nf3#
*

[Event "Englund Gambit"]
[Site "?"]
[Date "2020.05.28"]
[Round "?"]
[White "Bad"]
[Black "Traps"]
[Result "*"]
[ECO "A40"]
[PlyCount "16"]

1. d4 e5 2. dxe5 Nc6 3. Nf3 Qe7 4. Bf4 (4. Bg5 Qb4+ 5. Nc3) (4. Nc3 Nxe5 5. e4
$16) 4... Qb4+ 5. Bd2 Qxb2 6. Bc3 $4 (6. Nc3! Bb4 7. Rb1! Qa3 8. Nb5 (8.Nd5) 8...Bxd2+ 9.
Qxd2 Qxa2 10. Rd1 $16) 6... Bb4 7. Qd2 Bxc3 8. Qxc3 $4 Qc1# *

[Event "Tennison Gambit"]
[Site "Reti opening"]
[Date "2020.05.28"]
[Round "?"]
[White "Bad"]
[Black "Traps"]
[Result "*"]
[ECO "C50"]
[PlyCount "13"]

1. Nf3 d5 2. e4 dxe4 3. Ng5 Nf6 (3... Bf5 $15) 4. d3 exd3 (4... Bg4 $17) (4...
Bf5 $17) 5. Bxd3 h6 $4 (5... Nc6 $17) 6. Nxf7 Kxf7 7. Bg6+ *

See also: http://devonjuniorchess.co.uk/content/tarraschs-opening-trap-course-tactics