There are many kinds of puzzle mechanics, and in general, only a few of them are unsophisticated. As a rule, each game is a mix of various concepts and ideas. Nevertheless, let's try to identify some basic forms.
In word puzzles, the players try to connect letters or symbolic images into words or expressions. This is a very popular class of games and many of them were created long before the first electronic devices were born. Among the popular examples are Crossword, Rebus, Cryptog ram, Hangman, Ghost, Jotto, Anagram, and Scrabble. Some of them operate with words, while others manipulate letters. Dictionaries are used to check existing or correct spelling. There are many word puzzles for mobile devices; one of the examples is an excellent game QatQi (http://qatqi.com) by Zworkbench, which is both very intelligent and magically beautiful.