What is a Character in a Computer?
A character is a single letter, number, or punctuation in a text. In a computer, normally any text is just a sequence of characters, also called a character string. Anything that you can select individually on a text is a character. This includes, for example, spaces typed by pressing the space bar. A space ( ) is a character. Similarly, you can input a "new line" by pressing the Enter key, so a new line is a character as well.
What is a Character in Games?
In games, character normally means a human character, or an animal or monster character, specially if it talks. There are two special terms in this context. In role-playing games (RPGs), the player character, or PC, is a character a human player controls, while a NPC (non-playable character) is a character that the CPU controls.