Experience Meter

A meter that shows the current experience of a character, usually showing progress between two levels. This is obviously most common in games where experience is an important factor. However, it's not very common in an RPG, but is mostly found in MMORPGs. The color of this meter can be anything not used by the same game's Life Meter, Mana Meter or other main meters, and can vary in game depending on some factors. If the Level Cap is reached, the bar might disappear since it no longer serves any purpose.

Unlike the two other meters, it's rather uncommon that something might subtract experience rather than adding to it - except death. Remember: in MMORPGs, as opposed to Real Life, death equals stupidity instead of the other way around.

Examples of Experience Meter include:

World of Warcraft has a purple meter that turns blue when the character has been resting, which indicates double experience until a certain limit is reached (up to 1½ levels worth of experience, which requires weeks of real-time resting). The bar also has a light blue meter showing how much rested experience you can gain. This only affects experience for killing monsters though and neither affects nor is consumed by most other means of experience gains like completing quests.
- Hunter pets also have one, but it's only shown in their details and not quite as important, as they only need a fraction of their masters experience and never fall below 5 levels lower than him. Obviously, they can't outlevel him either.
- Players can also display their reputation for one faction underneath it (the option is called "show reputation as experience bar), colored according to the reputation level system (going from deep red for hostile to green from friendly onwards).
Battle for Wesnoth has a meter for every unit next to its Life Meter. The color of the meter is normally blue, white when the unit is about to level up and purple if the unit has reached its final advancement. It can still level, but instead of evolving into a different unit, doing so only gives the unit some extra health and heals it completely, which happens with every level up.
Pokémon has one for each Pokemon, in the fighting screen below the HP bar, since the Gold/Silver games.
City of Heroes has an experience bar measured in "bips" or "bubbles". As of a recent patch, it follows something similar to the World of Warcraft example above, granting bonus XP for time not played. Dying also results in experience "debt", where subsequent XP gains are reduced to half, the other half paying off the debt. With the myriad ways to either avoid or reduce debt, however, the experienced player is usually able to avoid it entirely.
- Patrol XP is built up while the character is logged off and works by adding a 1.5 modifier to XP gained from defeating enemies only, it doesn't apply to mission completion bonuses. Also, if you die while you have patrol XP built up it will automatically be used to pay off your XP debt.
Diablo II has one underneath your HP vial.
As Kingdom of Loathing gives XP out in all three of its stats, each of them can have a bar for this, as well as your main level XP bar (which is based on your 'main' stat).
Rare RPG example: Bowser's Inside Story has a flagpole for each character on the end-of-battle screen. The flags raise in proportion to the amount of EXP gained, and when they hit the top of the flagpole, a light flashes, signaling a Level Up.
The EXP bar in La-Mulana is an interesting example, given that the game is a platformer with no RPG elements. Killing enemies fills up the meter, which, when filled, just restores your health.
In Call of Duty: Modern Warfare 2, multiplayer, you have orange bars at the bottom of the screen. When they are full you get new equipment weapons or perks.
Dark Cloud and Dark Cloud 2 use XP bars for weapons: When the bar is full, weapon gains a level and more synthesis points
Same with later Ratchet and Clank games; weapons have their own experience bars that fill the more you use the weapon. When the bar is full, the weapon levels up (with much fanfare).
At least Fire Emblem: Mystery of the Emblem for the SNES shows your soldiers' experience bar graphically as they gain exp.
The Sonny games do this as well, showing XP graphically as well as numerically (as a percentage), with the meter gray unless a character levels up, at which point it will either turn yellow or blue depending on which Sonny you're playing.
Dungeons and Dragons Online has a "rank" system for XP. As you fill up your XP bars, you gain Action Points that can be used to gain Enhancements for your class. When you gain five ranks, you're ready to reach the next level.
Adventure Quest Worlds has two separate Experience Meters. The first, in green, fills up as you gain Class Points, and when the meter is full, your class ranks up. As you rank up in a given class, you gain more skills, and the highest rank you can have in a class is 10. The other meter, in purple, is your basic leveling meter, and levels up your overall character when it's full. Ranking up classes is comparatively easier than leveling up your character, especially as you get into the higher levels.