Conceptual confusion

jepombar

What the difference of pages residing on the server side and pages residing on the client side?
Aren't the html pages stored on the same server along side the php scripts? Don't both of them need the get "loaded" from a server. Wouldn't that make these html pages server side pages as well?

wilku

Pages are generally stored on server side - not on the client side. It's about when code in that pages are run. The "chronology" of getting the page is like this:
- browser sends request to the server (when user clicked on some link or entered an url)
- the server gets the page browser requested from disk and looks for some scripts in it.
- when server finds php code, this code is now executed, producing some data to be sent to browser; to server it doesn't matter if it's html, javascript etc. it is sending (php can echo some javascript for example - php is executed, javascript is sent without any execution, as text).
- browser receives data from the server (the same data that was produced by php script).
- browser parses html into some nice layout; when it finds JavaScript is now executed (if it's enabled in the browser).

So you see that there are two stages: first happens on the server (server-side), then the output is sent to browser, where second stage is taking place (client-side). Therefore php is a server-side language, JavaScript is a client-side language.

jepombar

So following this logic, there would be no point in caching .php pages since we still have to go back to the server to run the php code and wait for the response. So my question is do pages with php extension get cached?

If the answer is no, then a web site with all php pages will always take longer to load than one with html pages that uses ajax to get responses from the server as needed, right?

bradgrafelman

jepombar wrote:
So my question is do pages with php extension get cached?

They can be, yes - there are plenty of classes out there to help with caching.

Just because a page is written in PHP doesn't mean that it's necessarily so dynamic to the point where caching is pointless.

jepombar

So are there any tutorials to help with caching and php?