Meaning

Passed Hand Bidding

(P) - P - (P) - 2S

Not preemptive, some play this sequence shows 6-7 Losing Trick Count - not forcing but seriously invitational with a strong major suit

  P - 1H;
2S

Responder's jump after a passed hand shows a near opening hand with good trump support, one round forcing if playing fit showing jump bids

  P - 1S;
2C - 2D;

Playing Reverse Drury, partnership agreements vary (forcing, but partnership methods may or may not be game forcing)

One level Bidding

1H - 1S;

  P - 1D;
1S - P;

Responder's new suit is always forcing one round

Exceptions: when partner is a passed hand, opener may pass

1H - 1S;
1N - 2C;

1H - 1S;
1N - 3C;

After opener's 1 Notrump rebid, responder's non-jump is not forcing.

However, responder's jump bid in a new suit is forcing

1C - (P) - 1S - (2C);
P

When an opponent makes an intervening bid, the opener in the direct seat may pass - responder still has the opportunity to bid or perhaps double (which opener may convert to a penalty pass with length in Right Hand Opponents' suit and shortness in partner's suit

1C - 1D;
1H

Conceptually, responder can pass opener's 1 level rebid (perhaps holding 5-6 points); opener holding a maximum hand may make a forcing strong jump shift or appropriate jump in Notrump (opener's 2N rebid is invitational)

1H - 1N;

Playing 2/1, responder's 1 Notrump is forcing (6-13 points), unlike a 6-10 point signoff bid for Standard American players

1C - 1D;
1H - 1S;

A fourth suit 1S bid is natural showing 4 Spades by most North American players (2S becomes Fourth Suit Forcing), while many Europeans consider reverse this treatment

(1H) - X

Takeout double is forcing (seldom converted to penalty).  After responder's bid, opener's bid in a different suit show 17+ points, suggesting game when responder hold 7-8 points

1C - 1D;
1H - 3C;

Partnership agreement, usually invitational if playing Inverted Minors, otherwise may be forcing

Responder bids at the 1 level, opener rebids at the 2+ level

1D - 1S;
2C - 2N;
3D

After responder's 2N invitational rebid, opener's 3D belated rebid is forward going showing strength and a shapely minor

1D - 1S;
2C - 2H;
3S

Delayed support is game forcing (belated jump raise)

1D - 1S;
2C - 2H;

Fourth Suit Forcing (one round or game, partnership agreement)

1D - 1S;
1N - 2C;
2D/N

2C is New Minor Forcing, partnership agreement needed to distinguish opener's 2D versus 2N re-rebid on this auction

1D - 1S; 1N - 2C; 2D - 3S is game forcing (responder's direct jump rebid to 3S would be invitational)

1C - 1D;
2H

Opener reverses are forcing one round at the 2 level, except by a minority adhering to legacy methods (game forcing at the 3 level); also see Lebensohl over reverses

1C - 1D;
2C - 2H;

Responder reverses are typically game forcing

1D - 1S;
2D - 2H;

Responder's new suit is one round forcing by most partnership

1H - 1S;
2S - 3D;
3H - 3S;

After partnership major suit agreement, some play responder's new suit establishes a game force regardless of subsequent suit rebids (responder's 3S initial rebid would be invitational)

1H - 1N;
2C - 2S;

Ostensibly the Impossible 2S convention, game invitational with long unbid minor

1H - 1S;
2N - 3S;

Responder's major suit rebid is game forcing after opener's strong 2N jump (also see Wolff Signoff and New Minor Forcing)

1H - 1S;
3H - 3S;

After opener's jump raise, responder's non-pass bid is game forcing

1H - 1S;
4H

1H - 4H;

Opener's 4 level game rebid is strength showing, not a drop dead signoff bid.

However, responder's 4 level game jump is a drop dead bid.

Opener bids at the 1 level, responder bids at the 2+ level

1N - (2D) - 3x

Responder's 3 level bid is typically game forcing (see Lebensohl)

1N - 2C;
any - 3C/D;

Various partnership agreements (some play slam invitational in minor suit, others play drop-dead signoff or game invitational)

1H - 2C;
 

1H - 2C;
3H

Playing Standard American, two over one bids are one round forcing (responder promises a rebid); playing 2/1 the two over one sets a game force (or 4 of minor by some)

Playing any methods, opener's jump rebid is game forcing

1D - 2C;

1D - 2C;
2H

Forcing one round for Standard American players, game forcing by many 2/1 players - over 50 pages are devoted to treatments beginning with this sequence in Mike Lawrence's Workbook on the Two over One System.

Even if not initially not game forcing, many play opener's major suit bid show 16+ points (reverse-like), setting up a game force.

1D - 2D

Playing Inverted Minors, either one round or game forcing (see Criss Cross Raise)

1H - 2H;
3C

After a suit agreement, opener's new suit bid is one round forcing, typically a game try

1H - 2N;

Many play the conventional Jacoby 2 Notrump game forcing sequence showing an opening hand and good trump support, while this sequence is merely invitational for ACOL players

1D - 2N;

1S - 3S;

Invitational over minor opener according to modern methods; traditionalists play as game forcing and likely play game forcing jump raises as well (again invitational by most today)

1S - 2H;
3D - 3N;
4C

When partnership bids beyond a game contract, the new suit is forcing (4C is Gerber by some partnerships)

1S - 2D;
2N - 3S;

Responder's 2 level bid in a new suit (temporizing) followed by a belated 3 level major support may be either invitational or game forcing (where 2N shows extras)

1H - 2H;
3C

After a suit agreement, opener's new suit bid is one round forcing, typically a game try

1S - 2H;
3D - 3N;
4C

When partnership bids beyond a game contract, the new suit is forcing

1S - 2D;
2N - 3S;

Responder's 2 level bid in a new suit (temporizing) followed by a belated 3 level major support may be either invitational or game forcing depending on partnership methods (where 2N shows extras)

Bidding begins at the 2+ level

2D - 2S;

After partner's preemptive weak 2 opening bid, a common partnership agreement is responder's new suit bid is forcing one round (RONF - Raise is the Only Non Forcing bid)

2C - 2D/2H;
2N

Opener's 2N rebid is commonly played as invitational, non forcing after responder's waiting bid (or weak if playing 2H bust), most play responder may pass opener's 2N rebid but not a suit bid.

(2D) - 2H - (P) - 2S

After responder's overcall, advancer's new suit bid is forcing one round

3D - (P) - new suit

After partner's preemptive weak 3 opening bid, responder's new suit bid is forcing

Other bidding scenarios

(1D) - P - (P) - 2N

Strongly invitational, showing values above a 1 Notrump opener (not Unusual Notrump in passout seat)

Various cuebids

Cuebids are forcing, including Limit Plus Raise, Western Cuebid, Eastern Cuebid, Control Showing, Michaels Cuebid, Splinter Bids, Choice of Game Cuebid, All Purpose, Tops and Bottoms, Colorful, Unassuming (exception: Sandwich Overcall)