So far all my sites use mostly $\_GET's to get the data for a page. 

Ex: 

```
editad.php?posting_id=131

editaccount.php?user_id=2

```

-->is there a way to hide or be more secured about what the user can see? I don't want them to be just able to say type "editad.php?posting\_id=40" in the URL. I know I can use POSTS, but is there a way for GETs or not?

-->I pass along data through a GET, then validating that data by checking if the user's id is equal to the page's user's id. If they are equal, it would allow the user to edit that page, if not, it would only show that page. I also make sure a number is a number, a string a string, etc.
Is there any other way to make it more secure?