Hi,

I am sure that question has been asked many times before, but I can't find the answer. Is it allowed to use the game explorer during on line chess games ? 

Thanks

It is. The database is a static information source which diverges (like a book) and so is allowed to be used in correspondence games.

Thank you for your reply, Nytik.

I didn't know we were allowed to use external support when playing games.

Databases and opening books only, and in Correspondence Chess only -- no outside assistance is permitted in Live Chess.

Here is a simple presentation of the rules:

http://support.chess.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=17&nav=0,6

ARTREF: WHAT IS ALLOWED

Presumably this exception to the prohibition of the use of engines also applies to end-game table-bases, no?

(except by agreement of both players, where specifically arranged and must be UNRATED games e.g. in a tournament created for that purpose)

We are not allowed to use chess programs or chess engines such as Fritz, Rybka etc...

This is what chess.com says in the link I quoted  http://support.chess.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=17&nav=0,6

What are the rules for playing?

You many only have ONE Chess.com member account. You may NOT get any help from any person or any chess engine throughout the course of a game, including tablebases. You MAY use books, magazines, or other articles. You may also use computer databases (including Chess.com's Game Explorer). EXCEPTION: If both players agree for the use of a chess engine in an UNRATED game then it can be allowed. 

Hard to say. I would have thought that using tablebases made the contest pointless - assuming the tablebases were of equal strength.

Would you able to employ grandmasters to advise you?

I suppose that if both sides were using table-bases it would be clear as soon as you were in a position to check them what the outcome of the game would be so I guess they'd really only be a tool to decide the outcome once you got down to six remaining pieces.

I have to think that as long as the game is unrated and the terms are agreed to by both players before hand that the spirit of the exception is anything goes.

Except ESP, obviously.*

*Desperate attempt to keep controversy alive.

The reason tablebases aren't allowed but databases are, if anyone was wondering, is because databases are diverging whereas tablebases are converging.

With tablebases, you know exactly where the position will lead, along with its outcome, but with a database you are only following suggestions, possible good moves, and have no idea what the future has in-store results-wise.

Sorry to ask but then what is the difference between a tablebase and a chess program or chess engine like Fritz or Rybka ?

I've none of this sotwares but considering bying one soon or next Xmas (I haven't decided yet).

An endgame tablebase is a computerized database that contains precalculated exhaustive analysis of a chess endgame position. Tablebases have solved chess for every position with six or fewer pieces (including the two kings).

A chess engine is simply a program that can play chess. It can therefore find a 'best move' from any position. Most engines must be used in conjunction with a separate GUI e.g. XBoard (Linux) and WinBoard (Windows).

A chess engine can use a tablebase to increase the power of its endgame play (provided there are no more 6 pieces left on the board).