Confused about ChessBase I'm really confused about the differences between the products that ChessBase offers. For example, on the website, Deep Fritz is said to be an engine. But after a bit of research, it turned out that it holds a database, a multimedia directory, a playchess.com client, and a tactics trainer! ChessBase is only said to be a database although it also features training courses. Also, ChessBase markets Houdini which is said to be "the world's strongest engine". So, if it is, doesn't that make Deep Fritz rubbish ? Please clear my confusions.
Deep Fritz 14, Houdini 4, Komodo 9 and Rybka 4 all use the same Graphic User Interface (GUI).  It allows you to blundercheck, do full game analysis, calculate elo ratings for sets of games.  It has a Handicap and Fun mode for dumbing down these engines, so you have a chance.  You can also play timed games, and adjust the engine's style.  There is also a hotness meter that shows you how sharp or dynamic the position is.

ChessBase 13 cannot do timed games or full game analysis, but it can do infinite analysis.  It can create opening and endgame theme keys, and has a search mask for locating games with certain traits quickly.  Lists of games can be sorted by player name, year, result, elo rating, tournament just by clicking on the header.

Komodo 9 is probably stronger than Houdini 4 which is stronger than Rybka 4 which is stronger than Deep Fritz 14.  Some people like the slightly weaker engines because they believe they have special characteristics, for example a sharp or solid style, more human feel, or the like.

Both ChessBase and the engine GUIs allow you to annotate games, add variations, draw arrows on the board, watch videos, do infinite analysis, play on Playchess.  The Engine GUIs have some basic database functions.  The Engine GUIs are mainly for playing against, and ChessBase is for building an opening repertoire, and preparing to play specific opponents.