Equilibrium refers to a particular state wherein there is no net change that is occurring. Equilibrium involves something which is regarded as balanced or stable, and this state is very rare. Typically, this state only happens for very limited periods of time until another factor interfere with the stability.

The concept of equilibrium is essential in the field of science and is generally used to refer to a balanced state. Because it is normal for things to change either slowly or rapidly throughout time, it can be difficult to achieve a stable state. For instance, the human body aims to establish a stable state called the homeostasis, which is critically important for a person.

In the field of chemistry, there exists a term called dynamic equilibrium, which is used to refer to a particular case wherein opposing reactions are used to balance the activity that occurs in a specific solution, in order to maintain its stability. To put it simply, you can imagine two persons placed on each side of a seesaw. If each of them exerts an equal amount of force against their own sides, the opposing forces that were exerted will balance each other and the seesaw will not move, thus achieving a state of equilibrium.

In game theory, there is also a type of equilibrium called symmetric equilibrium, which involves all game players utilizing the same strategy. Additionally, this concept is also important in the field of mathematics. It can be used to investigate complex problems and provide explanations regarding the way economic systems function.

In order to support the living things, the natural environment also attempts to sustain a balanced state or a state of equilibrium. Furthermore, researchers in the field of biology are also concerned about hypothetical scenarios, which involve this concept. For instance, they are interested to know what could possibly happen when evolution comes to a point wherein no net change is occurring and the evolution of living things comes to a halt.