"Knowing" Ajax isn't a skill, like riding a bike or knowing what the $() operator does - it's understanding a concept. In short, it's a term that describes a d

"Knowing" Ajax isn't a skill, like riding a bike or knowing what the $() operator does - it's understanding a concept. In short, it's a term that describes a design pattern where some Javascript makes an asynchronous HTTP request in the background without interfering with the display and behavior of the existing page, receives the response, and then does something with that information. Now that you've got what it means, the question becomes "How do I implement that?", which is much easier to deal with. For this, just keep digging through the jQuery examples and tutorials (if that's the Javascript route you're taking). Find a trivial example, get it running on your host, and then start experimenting with it. Once that's down, repeat with a more complex example. Read some more articles from different authors. Make your own examples. Repeat. As for the broader question of when you should learn it (or anything else), the answer for things like this is always the same: when you feel in the mood for learning something new.