I like to use puzzles as a way to sharpen my mind. Do you have a favorite type of puzzle?
I do too.  My favorites are crossword puzzles and logic-type puzzles, like Tetris.  What about you?
I like doing word puzzles and Sudoku mostly
Sudoku solving algorithms
A standard Sudoku contains 81 cells, in a 9×9 grid, and has 9 boxes, each box being the intersection of the first, middle, or last 3 rows, and the first, middle, or last 3 columns. Each cell may contain a number from one to nine, and each number can only occur once in each row, column, and box. A Sudoku starts with some cells containing numbers ("clues"), and the goal is to solve the remaining cells. Proper
Puzzle book
A puzzle book is a type of activity book which contains a collection of puzzles for the reader to complete. Puzzle books may contain puzzles all of simply one type like (e.g. crosswords, sudoku, or wordsearch) or a mixture of different puzzle types. Puzzle books may be aimed for adults or children. Puzzle books can be used for many purposes such as education or purely for entertainment. 
Crossword puzzles first appeared in England during the 19th century. The first crossword puzzle book was published in 1924 by