В hand history фиксируется вообще все: кто делал ставки, кто и когда повышал, какие приходили карты и т.д.

Примеры см. на http://forum.cgm.ru/lofi/f20/th3195.html и
http://www.cgm.ru/handconverter/examples.html :

Stage #384883147: Holdem Normal $1/$2 - 2006-06-19 01:13:22 (ET)
Table: K STREET (Real Money) Seat #9 is the dealer
Seat 9 - OLLIO ($29 in chips)
Seat 2 - ILUV_H8POKER ($7.51 in chips)
Seat 3 - PROFPLEISCHNER ($40 in chips)
Seat 4 - SHOTGUNBOB ($110.37 in chips)
Seat 5 - KABUR ($20 in chips)
Seat 6 - MRASKEW ($8.37 in chips)
Seat 7 - SKIN ($33 in chips)
ILUV_H8POKER - Posts small blind $0.50
PROFPLEISCHNER - Posts big blind $1
KABUR - sitout (wait for BB)
*** POCKET CARDS ***
Dealt to PROFPLEISCHNER [3s 3h]
SHOTGUNBOB - Folds
MRASKEW - Folds
SKIN - Folds
OLLIO - Folds
ILUV_H8POKER - Raises $1.50 to $2
PROFPLEISCHNER - Calls $1
*** FLOP *** [Jd 7h Jc]
ILUV_H8POKER - Bets $1
PROFPLEISCHNER - Raises $2 to $2
ILUV_H8POKER - Calls $1
*** TURN *** [Jd 7h Jc] [8d]
ILUV_H8POKER - Checks
PROFPLEISCHNER - Bets $2
ILUV_H8POKER - All-In(Raise) $3.51 to $3.51
PROFPLEISCHNER - Calls $1.51
*** RIVER *** [Jd 7h Jc 8d] [4d]
*** SHOW DOWN ***
ILUV_H8POKER - Shows [10h Ac] (One pair, jacks)
PROFPLEISCHNER - Shows [3s 3h] (Two Pair, jacks and threes)
PROFPLEISCHNER Collects $14.27 from main pot
*** SUMMARY ***
Total Pot($15.02) | Rake ($0.75)
Board [Jd 7h Jc 8d 4d]
Seat 2: ILUV_H8POKER (small blind) HI:lost with One pair, jacks [10h Ac - B:Jd,B:Jc,P:Ac,P:10h,B:8d]
Seat 3: PROFPLEISCHNER (big blind) won Total ($14.27) HI:($14.27) with Two Pair, jacks and threes [3s 3h - B:Jd,B:Jc,P:3s,P:3h,B:8d]
Seat 4: SHOTGUNBOB Folded on the POCKET CARDS
Seat 6: MRASKEW Folded on the POCKET CARDS
Seat 7: SKIN Folded on the POCKET CARDS
Seat 9: OLLIO (dealer) Folded on the POCKET CARDS

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В сабже вместо перечней типа [Jd 7h Jc 8d 4d] идут графические изображения карт - так, разумеется, нагляднее
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Как я понял, hand history генерируется уже после игры, чтобы можно было проанализировать действия всех игроков