What is the difference between client-side and server-side testing when executing various tests?

as per my question, i am wondering what differences are there when we are performing tests for the client side, as compared to performing tests on the client side?

For example, testing javascript on the client side versus testing server 开发者_JAVA技巧side code?

When you are testing server side code you are testing the logic and readiness of your application. When you are testing Web Side code you are doing end to end testing.

Meaning that if you test server side code you cannot be sure that you know that the client side code will behaive. For example you could get a bad result from the server but display it in the nicest way possible. The data would still be bad.

Your server would still fail but your script would still pass.