Chess Terms


Chess engines rule the chess world in terms of raw strength. According to the September 2020 Computer Chess Ratings List, there are 60 engines with a rating of 3000+. The engine that has been around the longest is HIARCS.

Let's learn more about HIARCS. Here is what you need to know:


HIARCS, which is an acronym for higher intelligence auto-response chess system, is a proprietary chess engine. It was developed by Mark Uniacke in 1980 when he was only 15. In 1991 HIARCS was available for PCs, and in 1996 it became marketed by ChessBase and was included in the Fritz graphical user interface (GUI). Since 2012 it has been sold with its own GUI (Chess Explorer) and is available for Mac OS and Windows.

HIARCS has multiple world titles and has been on the computer and engine scene for over 40 years. It remains a strong chess engine with a rating of 3222, according to the July 2020 ratings list of SSDF (the Swedish Chess Computer Association), and is in the top 50 engines on the Computer Chess Ratings List (CCRL).

HIARCS chess engine
HIARCS logo. Image:

HIARCS Accomplishments

HIARCS won the World Microcomputer Chess Championship in 1991. In the following year, it won the gold medal at the Computer Olympiad. HIARCS won its second World Microcomputer Chess Championship in 1993. In 2003 it drew a four-game match with GM Evgeny Bareev, who was ranked number eight in the world at the time.

GM Evgeny Bareev in 2008. Photo: Stefan64, CC.

In 2008 HIARCS won the World Computer Chess Championship (after Rybka was stripped of its title). It also won the World Chess Software Championship in 2011 and then again in 2013.


In the first game example, we see HIARCS facing off against IM Sofia Polgar (a sister of GM Judit Polgar and GM Susan Polgar), who sacrificed a pawn for good compensation in the middlegame with 18...d4. However, HIARCS defended like a machine (pun intended). HIARCS was able to keep the extra material and converted the endgame easily.

In the second example game, HIARCS defeated the engine Jonny in the 2009 World Computer Chess Championship. HIARCS played a strange-looking piece sacrifice where its compensation was difficult to determine:

HIARCS chess engine
It isn't immediately clear why HIARCS sacrificed their knight in this position.

It takes more than five moves until obvious compensation for the piece is on the board, as the black king is stuck in the center. Black gives the extra piece back on move 26, and HIARCS cruises to victory in the knight-and-pawn endgame. After 44.Kxa6, HIARCS has three connected passed pawn versus a lone knight.


You now know what HIARCS is, what it has accomplished, and more! Head over to to watch top engines battle at any time on any day!

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