What does it mean when something is described as "immutable"?

When something is described as "immutable," it means that it is fixed and unchangeable. This term often refers to conditions, concepts, or attributes that remain constant and cannot be altered. In various contexts, such as philosophy or computer science, "immutable" emphasizes the idea that once established, certain elements cannot be modified or influenced by external factors. The understanding of immutability is crucial in discussions where stability and permanence are essential characteristics, contrasting with concepts that imply changeability or adaptability often associated with the other options provided.