What is the meaning of tinyint(N)?
Data-wise, tinyint(1), tinyint(2), tinyint(3) etc. are all exactly the same. They are all in the range -128 to 127 for SIGNED or 0-255 for UNSIGNED. As other answers noted the number in parenthesis is merely a display width hint.

You might want to note, though, that application=wise things may look different. Here, tinyint(1) can take a special meaning. For example, the Connector/J (Java connector) treats tinyint(1) as a boolean value, and instead of returning a numerical result to the application, it converts values to true and false. this can be changed via the tinyInt1isBit=false connection parameter.