How to find the monotonicity of exponential function? What is the meaning of "same increase different decrease" with a law? Can you give me a few examples?

How to find the monotonicity of exponential function? What is the meaning of "same increase different decrease" with a law? Can you give me a few examples?

How to find the monotonicity of exponential function?
y=a^x
If a > 1, then the function increases monotonically, if 0