Experience

Experience, commonly abbreviated as Exp or XP, is a measure of progress in a certain skill. It is generally obtained by performing tasks related to that skill. After gaining a certain amount of experience, players will advance to the next level in that skill, which can result in new abilities, items, and other achievements. You can earn experience by training skills, completing quests (certain quests give experience rewards in certain skills) or playing minigames.

Leveling up
Each time you gain a new level in a skill, you will require more experience for the next level than needed to reach this one. For example, getting level 2 in a skill will require 83 experience points, while getting level 3 (considering you have 83 experience already) will require 91 more experience points. Each level you advance will require approximately 10% more experience than the previous one. The total amount of experience between level 98 and 99 is 1,228,825 experience!

The following table shows the relationship between level, the experience required for that level, and the experience difference from the previous level:

Boosts
The experience you gain can sometimes be boosted. For example, smelting a gold bar usually gives 22.5 experience points. If you smelt gold bars while wearing a pair of goldsmithing gauntlets, you will receive a bonus of 33.7 experience points, for a total of 56.2 experience points per bar smelted.

However, there are few ways to boost the experience you gain in 2006Scape.

Limitations
The amount of experience you can earn in a skill is not infinite. Once you gain level 99, you will continue earning experience for each skill-related activity you do. Level 99 only requires 13,034,431 experience, while the maximum amount of experience you can earn is 200,000,000 experience points.

The experience limit exists for a reason. The maximum number existant in a 32-bit Java application is 2,147,483,647. That's also the maximum amount of any stackable item you can have at a given time. Note that this also applies to the items that don't stack in the inventory, but stack in the bank. Because of the fact that, sometimes, you can get a lesser amount of experience than 1, that number is divided by 10 (burying bones gives 4.5 exp). Therefore, the maximum amount of experience attainable would be 214,745,364.7 experience points. However, Jagex made it so that the number is 200,000,000, because it looked better.