Where to write script "Browser versus Server Script"?

At times there comes a question as where to write code at Browser level or at Server level?

So to come up with the answer here are the differences between Browser and Server Script:

Browser script is used in the following scenarios:

• When we require communication with the user (to show some informative message using popup or to get some response like Ok, Cancel which is used in dialog box)
• Interaction with desktop applications.
• Data validation and manipulation limited to the current record.
• Browser scripts are stored as .js file.

Server script is used in the following scenarios:

• Query, insert, update, and delete operations.
• Access to data beyond the current record and to build complex logic.