3. Client side processing pros and cons

Advantage

• Web traffic is reduced and so less bandwidth is used.
• Reduces the load on the server as it does not have to do the processing.
• Helps ensure that data sent to the server passes validation rules.
• Interactive widgets, such as a pop-up calendar assists the visitor to enter data correctly.
• No delays in processing local data.

Issues

• The browser must support Javascript (most do)
• Javascript has to be enabled in order to run (some users and admins turn it off).
• Page loading is slower as the Javascript script has to be loaded by the browser.
• Search engines will find it difficult to index a JavaScript-heavy page, as much of the content is created as the page loads.
• It needs technical skills to write JavaScript code from scratch, although there are plenty of JavaScript libraries such as JQuery available that reduce this burden.