I have heard of programatically difference b/w
POST in web applications. Asking in curiosity which is more secure,
GET method or
POST method in web applications, I expect answers in terms of protocols too (i.e in
POST is more secure than GET for a couple of reasons.
GET parameters are passed via URL. This means that parameters are stored in server logs, and browser history. When using GET, it makes it very easy to alter the data being submitted the the server as well, as it is right there in the address bar to play with.
The problem when comparing security between the two is that POST may deter the casual user, but will do nothing to stop someone with malicious intent. It is very easy to fake POST requests, and shouldn't be trusted outright.
The biggest security issue with GET is not malicious intent of the end-user, but by a third party sending a link to the end-user. I cannot email you a link that will force a POST request, but I most certainly can send you a link with a malicious GET request. I.E:
I just wanted to mention that you should probably use POST for most of your data. You would only want to use GET for parameters that should be shared with others, i.e: /viewprofile.php?id=1234, /googlemaps.php?lat=xxxxxxx&lon=xxxxxxx
POST just puts the information in a different place (request message body) than GET (url). Some people feel like the latter exposes more information, which is true for some points (read down in the edit). From a point where an attacker would like to intercept your traffic, POST would be equally hard/easy for an attacker as for a GET.
If you want security so your request aren't exposed when it leaves end and start points, use SSL (https).
A valid point of Gumbo and Ladadada, logging of GET requests can happen more frequently than POST requests. For instance in the history of a browser (if you share that browser with someone else).
So this means you shouldn't be putting sensitive data in a GET request as a GET request might be exposed to people who are screenwatching.
As @Gumbo says URLs are logged and appear in more places thus GET requests are a little more insecure than POST requests. The point is that a lot of people think that POST requests are much more secure than GET reqs because they can see the data directly in the URL but using, for example, a proxy software that intercepts browser requests anyone can view and alter POST data.
Another point is that you have to think where do you use GET and POST because GET should be used only for operations that do not alter database information, only request or read information and POST data should be used when data are going to be altered. Some web scanners click on every link automaticaly (usually GET requests) and not in buttons or forms (usually POSTS requests) avoiding altering the database but if for example you put a delete operation after a link you have the risk that the link could be clicked by more automated tools more easily.
Obviously, web scanners also can "click" or follow buttons and forms but usually they differenciate and this behaviour could be modified to spider the web safely.