There are various online sources available within the Opening Explorer from the HIARCS Chess Server. These online sources provide chess moves and statistics depending on the product type and book subscription you have chosen:
- GM - this is a statistical opening book of chess moves played by Grandmaster over the board games. This online book is available to all customers for at least a year after purchase.
- GM+ - this is a statistical opening book of chess moves played by International Masters and Grandmaster in over the board and correspondence games. This online book is available to Deep HIARCS Chess Explorer customer for at least a year after purchase. An example of the Online GM+ book is given in the screen shot below.
- Tournament - this is a statistical opening book of chess moves hand tuned from the very best games played. It has contribution from IMs and GMs and the very strongest chess players. This online book is available to HIARCS Book subscribers and is the same as delivered as part of the HIARCS book subscription and is known to be the strongest commercial opening book and has been for a number of years.
Each online book is a regularly updated tree of chess moves, statistics and games from different sources. Updates to the online books are automatically and seamlessly handled by HIARCS Chess Explorer and the HIARCS Chess Server.
You can access statistics about the online source by moving the mouse cursor over the Source selector when an online source is selected, you will then see a book stats pop up:
From v1.8 the book stats pop up now shows the last date the book was updated (where available).
Our online books are updated regularly and we expect to grow our online book sources over time.