If you are a web programmer then you already know what the term “view source” means. But if you are someone who is new to creating web sites or just someone who is casually reading this article then you probably have no idea what that means. To “view the source” means that you are able to look at the source code which creates the actual web site. Well, you are able to see the client side source code. There is still source code that runs on the server of the web site that you are visiting that you will not be able to see.
But a sometimes when a web site has this set up, they do not want people to see that they are doing something shady. A lot of sites which have XSS attacks do not allow you to see the source code. So if I were you I would be careful for any site that blocks this capability.