Prevent caching of HTML page [duplicate]

Answer 1

The Codesnippet you showed makes the browser load the website everytime it accesses it, which is useful if you perform frequent updates, but still have a static page.

In case you want it to perform live updates, like it does for example in a (g)mail account, you need to make it refresh (parts of the page) itself. Use Javascript in this case, like it is shown in this question or an ajax call.

$('#something').click(function() {
    location.reload();
});