A class is something that represents a hobby or profession. As you gain levels in a class, you will gain new Skills, enabling you to do things that you would not be able to do normally. Leveling and gaining a class relies on mentality - if you are convinced that you cannot cook, or you do not find cooking to be important, for example, it is unlikely that you will ever gain a [Basic Cooking] skill, regardless of your actual skill in cooking - an example of this can be seen with Erin Solstice's lack of the [Tactician] class, despite her skill in chess.
The majority of people reach Level 20 in at least one class over the course of their lives. Much less individuals manage to reach Level 30; A handful in each town; a few dozen in a city. Few people ever reach Level 40, and they tend to be quite famous. People who have reached Level 50 or above are generally known throughout the world.
“All those that Think—Feel. From Feeling do we Act. It is in Action that we Level. All those who Think have a Class. And it is in that Class which we find destiny.” (Book of Levels)
Leveling comes from learning, and trials. Those who consistently do the same will not level. More importantly, Classes are based on what a person pursues. In Erin's case, by regarding chess solely as a game, in contrast to someone who considers tactical applications, like in warfare, she won't level, no matter how good she is. 
Not everybody with the same class gets the same skills. It depends on what the person needs and desires for the system to decide which skills to hand out.
Class Change Edit
It is possible for classes to receive a different name later on. One reason for a change could be due to a specialisation in a certain field. A [Warrior], for instance, might decide to focus on using solely one specific weapon, like a spear, which might result him becoming a [Spearmaster] after having reached a high enough level. Another reason would be for to simply advance. One example for such a case would be a [Tactician] becoming a [Strategist]. That said, depending on the skills a person's class might never change, no matter how high it is. 
Known Changes: Edit
- [Tactician] → [Leader] or [General]
- [Warrior] → [Spearmaster], [Swordslayer], [Knight], [Vanguard]
- [Skeleton Warrior] → [Skeleton Knight]
- [Lord] → [King], [Queen]
- [Tactician] → [Strategist] → [Grandmaster Strategist]
- [Queen] → [Supreme Matriarch]
Class Merging Edit
It is possible for two classes to merge to create a new, hybrid class. For instance, a [Warrior] and a [Strategist] class may merge to form a [Commander] class. Class merging is rare, and it may require enough levels in both classes and/or fulfilling rare conditions.
Known Merging: Edit
- [Warrior] + [Strategist] = [Commander]
- [Warrior] + [Rider] = [Dragoon]
Cultural differences Edit
The name of the same Class can vary depending on the culture. For example, a [Warrior] could be a [Fighter] in a different culture. 
Known Cases: Edit
- [Warrior] - [Fighter]
- [Knight] - [Axemaster]
- [Cryomancer] - [Ice Mage]
Ryoka has specualted that there is a hard level cap or soft cap of 100. That theory has been supported by Klbkch review of several hundred individuals with high levels, whose cumulative level rarely approaches one hundred. Furthermore, that research has shown that individuals with more than two classes rarely surpass Level 30
People have become in certain areas narrow-minded due to the system. If one does something without having a class in that area, one already expects to be a failure in it.
- The Book of Levels, a book that was originally written nearly a thousand years ago, is part of the education of any child, which teaches them the essence of leveling.
- It was hinted by the Faeries that the system was created by the Gods.
- Some people worship levels instead of Gods. In some places leveling is preached and those with the highest level are even worshiped. Also, some speculate that each person has a maximum level , and when that level is reached, then they have also reached the end of their life.
- A person gets a better-than-average skill at Level 20.
- In Issrysil, once a person gets past Level 30, they becomes approximately one of a thousand on the continent. Their skills become in such high demand that they earn much more money than anyone else. Anyone with a class that involves managing land or selling or buying goods can earn thousands of gold coins each month.
- Although usually almost everyone reaches Level 20 before they die.An exception to the rule is the [Mage] class. People possessing that class rarely reach even Level 20, which is the result of a lack of a centralized education.