Class has several important meanings:

1. A group of students who learn together, or the time when they meet. Your math class might have 25 students, and it meets every morning at 9:00. When someone asks “What class do you have next?” they're asking about your upcoming lesson. The word can also mean all the students who graduate in the same year, like the class of 2025.
2. A category or group of similar things. Scientists organize animals into different classes: mammals form one class, reptiles another, and insects another. When you fly on an airplane, you might sit in economy class or first class, each offering different levels of comfort and service.
3. A level of quality or skill. A world-class athlete competes at the highest level. When someone does something with class, they do it with style, grace, and dignity. A person who shows class treats others with respect and handles difficult situations with composure. This meaning suggests excellence and good character.

The phrase in a class of its own describes something so exceptional it stands alone. A performance in a class of its own surpasses all competition.