Short answers, pulled from the story.
Gary Gygax and Dave Arneson created the concept of experience points in Dungeons and Dragons during the early 1970s. They designed the system to track character survival and learning rather than to create a universal metric for digital progress.
Lawrence Schick proposed the abbreviation XP to resolve a conflict with electrum pieces in the early 1970s. This change allowed the game to be published on schedule and established the three-letter code as the standard language for measuring growth in video games and tabletop role-playing games.
RuneScape imposes a hard cap of level 120 which requires over 104 million experience points to reach the maximum tier. This system creates a non-linear difficulty curve where characters must seek increasingly dangerous challenges to continue their ascent.
The term perk entered the gaming lexicon in 1997 with the release of the role-playing video game Fallout. This mechanic introduced permanent bonuses that unlock progressively as a character gains experience allowing for deep specialization in specific areas of gameplay.
Remorting allows a player to voluntarily reset their character to level one while retaining certain advantages that were previously inaccessible. This mechanic originated in MUDs where players could become immortal administrative staff and offers a way to break the cycle of power leveling.