Short answers, pulled from the story.
Character creation is the process of defining a player character before a role-playing game begins. The result is recorded on a character sheet that may include physical, mental, psychological, and social attributes, skills, personal history, appearance, and possessions. It is the first step taken by players, as opposed to the gamemaster, in preparation for a game.
Random generation uses dice rolls to determine character statistics, allowing the full range of values but giving players little control over their scores. Point-buy systems give players a pool of character points to distribute among statistics, with higher scores costing more points, allowing deliberate character building. Both methods appear in different editions of Dungeons and Dragons.
Traveller, Empire of the Petal Throne, and Harnmaster use narrative generation, as do the computer role-playing games Mount and Blade and Darklands. In this technique, players simulate their character's life through checkpoints such as early education, young adulthood, and career tours of duty before play begins.
Dungeons and Dragons introduced the mandatory character class concept, in which a character's class provides both direction and limitations during character creation and throughout the rest of play. This system was later adopted by all d20 System games and by Palladium Books' Megaversal system.
The Hero System (including its predecessor Champions), GURPS, the World of Darkness series, and the Amber Diceless Roleplaying Game all use point distribution to determine character statistics. Some editions of Dungeons and Dragons also include an optional point-buy method alongside their default dice-rolling rules.
Character advancement is the improvement of a character's statistics after the game begins, typically by spending experience points or gaining a new experience level. It uses similar rules to character creation, but changes are incremental rather than wholesale.