Latest On Chess Engines

     There are many engine rating lists out there, but my personal preference is the CCLR (Computer Chess Rating Lists) list. Another good site is CEGT (Chess Engines Grand Tournament). In any case, here’s a look at some of the top rated engines these days. Also, some links to terminology that may be helpful. 
     I think the only reason anyone would use any engine other than Stockfish, which is still the one to beat, is someone who plays high level correspondence chess and needs a second opinion from an engine that evaluates positions differently or else somebody who just likes to tinker with engines.  Looking at both of the rating lists reveals that all the engines have a poor record against Stockfish.

Fortress 
Fischer Timing 
Enhanced Forward Pruning 
Generating legal moves efficiently 
Alpha-beta Pruning 
Principal Variation Search
Bitboards 
Rotated Bitboards

OPEN SOURCE:

Stockfish 
Stockfish is based on another open source chess engine named Glaurung. It features aggressive pruning and late move reductions.
Suger Xpro 
SugaR is derived from Stockfish, and supports up to 128 cores. The SugaR engine defaults to one search thread, therefore it’s recommended to inspect Threads UCI parameter to make sure it matches the total number of CPU cores.
Ethereal 
Ethereal is an open source engine influenced by Stockfish, MadChess, and Crafty. One reviewer called its play dynamic and profound and said its style reminded him of a coffeehouse player.
Andscacs 
It uses magic bitboard to speed up the attack calculations. It applies a principal variation search with transposition table inside an iterative framework. In order to make the engine more powerful and efficient, about 200 evaluation features were optimized with 750,000 positions. 
Booot 
Booot determines sliding piece attacks with rotated bitboards, and lazy SMP, PVS with search enhancements like late move reductions, null move pruning, and internal iterative deepening. 
Xiphos 
This is an engine that utilizes bitboards with ERLEF mapping. It also uses sliding piece attacks. Laser Chess For more information on this engine visit HERE.
Gull 
An engine that applies magic bitboards to determine sliding piece attacks and features Syzygy Bases, PDEP bitboards and Lazy SMP. 

FREE: 
Fire 
Fire used to be open source but later became a closed Windows executable, available for new Intel processors. It features magic bitboards, Syzygy tablebases, configurable hash, and multiPV. 
Fizbo 
I don’t have much information on this engine, but you can visit the site for full details.  
Schooner 
Schooner uses alpha-beta search, late move reductions, principle search window (PVS), and single hash entry. 
Equinox 
Equinox has taken ideas from open source engines like Stockfish, Crafty, and Ippolit. 
Critter 
The engine features null move pruning, forward pruning, principal variation search, parallel search with up to 8 threads, blockage detection in the endgames, and supports Gaviota tablebases. 
Hannibal 
Hannibal incorporates ideas from earlier engines (Twisted Logic and Learning). It has a good understanding of material imbalances and has excellent endgame knowledge. It understands fortresses, trapped pieces and will sacrifice material for the initiative when conducting a K-side attack. Interesting is that it is tuned for the Fischer time control. 

COMMERCIAL: 
Komodo 
Komodo was derived from an older search engine, Doch. It has a different positional style as it relies on evaluation, instead of depth. The engine supports up to 64 cores, Syzygy endgame tablebase, and Fischer random chess. Kodomo lets you save engine’s analysis of a position so you can check it later and resume analysis. You can also control how the engine makes long-term sacrifices of P-structure. 
Houdini 
Houdini is known for its positional style, ability to defend strongly, tenacity indifficult positions and ability to escape with a draw. To date, it has won 3 seasons of Top Chess Engine Championship. 
Deep Shredder 
Shredder is a commercial chess engine built in 1993 that has won more than 20 titles. Deep Shredder is the multiprocessor version of Shredder and comes with a graphical user interface and is compatible with other UCI engines. It’s ultra-fast and highly intelligent. In selecting moves, most engines use brute force (they try to see everything for many moves ahead), but today programs today don't evaluate as many positions as possible; they try to “understand” a position and cut out moves that don’t seem to fit. Shredder's play is extremely solid positionally and some say it is human like. 
Fritz 
This engine has been around for years. For all the particular see HERE.  
Chiron 
The latest version has been tuned deeply, especially in terms of passing pawns and mobility, and several search enhancements have been introduced, like lazy symmetric multiprocessing, forward pruning, and NUMA awareness.