Given some questions and answers from an online course, classify the type of questions.
Q: What is an interior angle?
A: An interior angle is an angle inside a polygon that is formed by two adjacent sides.
Type of question: Definition.
Complete the following task based on the instruction and optional input provided.### Instruction:
Given some questions and answers from an online course, classify the type of questions.

### Input:
Q: What is an interior angle?
A: An interior angle is an angle inside a polygon that is formed by two adjacent sides.

### Output:
Type of question: Definition.