Latency and Processing Time and Response Time

What is the difference between Latency, Processing Time and Response Time ? 

What is Latency? 

Latency is the delay incurred in communicating a message (the time the message spends “on the wire”).

What is Processing Time?

Processing time is the amount of time a system takes to process a given request, not including the time it takes the message to get from the user to the system or the time it takes to get from the system back to the user.

Processing time can be affected by changes to your code, changes to systems that your code depends on (e.g. databases), or improvements in hardware.

What is Response Time?

Response time is the total time it takes from when a user makes a request until they receive a response.

Response time can be affected by changes to the processing time of your system and by changes in latency, which occur due to changes in hardware resources or utilization.

Latency + Processing Time = Response Time