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What are the different ways one can use to store form/input/user preferences data on the web site server?

I'm new to web development and I'm trying to make small projects to better understand how javascript works and how interactive websites are made. So I wanted to make a simple website that would save links that you would enter using input/form submission. but what are the ways which I can use to store it on the server so when I open the page next time the website retrieves the saved information and displays it?
I know this question is pretty open, but I'm really lost in this part of web development because I'm seeing too many completely different things on the internet like PHP, ASP.net and what not. Can someone help me out?
It would be very thankful if someone can send me a link to a related tutorial or some similar resource, as well.

If you to do that, you will need a server side program with a Database.
Here is a tutorial for PHP, a popular language to do web pages http://www.w3schools.com/php/

When you submit your data in the form, That data will be sent to the file mentioned in the action attribute of the form. Now, each input element of your form will have a name attribute which you can use to refer as a key in your GET or POST super global array depending on the method attribute of your form tag.
I know it may sound confusing without example. But, This is explained at many links on the web. Try searching for form submission with post.

Decide on which technologies that you want to work with. I prefer you to use ajax with instead of just using javascript.
Link for flask tutorial http://www.fullstackpython.com/flask.html

Store the data in the client side is much simple I think. While storage in client, you can use localStorage sessionStorage and cookie.
localStorage you can storage whatever you want and it has no expiration time
sessionStorage the difference between localStorage is that it has a expiration time, A page session lasts for as long as the browser is open and survives over page reloads and restores
Cookie is much simple and can store limited value in string format

How to pass data between two pages with Javascript

I've seen several other questions on SO that are similar to this, but none of them are really what I'm looking for, so hopefully this won't be seen as a duplicate.
I have a client-side Javascript/HTML5 web application built with jQuery Mobile. I am finding that performance can be quite slow and it was suggested that having too much going on in the DOM could be the cause. My app does have several data-role="page" divs that could be bulking up the DOM in a single html page. I'm trying to split my app into several html pages to improve performance, but I want the experience to be seamless for the user. This means I will need to pass Javascript variables between the physical html pages within my app.
So far I've seen the following options in my searching:
Use a query string in the url going to the other pages. - I'm not sure I want my users seeing a what could be a rather large and confusing query string in the address bar.
Use server side code like ASP.Net or PHP to handle postback data. - I'm open to this, but I'm not really sure how it would work. I don't want to convert my html pages to aspx or php files. Could I have a simple server side script that could embed the postback data into a regular html file?
Use Cookies to store relevant data. - I'm not to sure of this one either because the majority of my users are in enterprise environments that may limit cookie usage.
Are there any other methods for accomplishing this? At this point, I'm leaning toward some sort of server side processing. If that is the best method, could someone point me in the right direction for figuring out how to do that?

Try out Local Storage or Session Storage http://www.w3schools.com/html/html5_webstorage.asp

Local Storage would be a way to go if you are HTML5 compliant. It will store values, reduce the calls to any server until you are actually ready to update all the info and the info will be present even when the browser is closed; use session storage or JS like this
window.onbeforeunload = function() {
localStorage.removeItem(key);
return '';
};
if you need to clear local storage of sensitive info on closing the browser.
Remember that anything you pass into local storage will come out as a string so you will need to convert it to the appropriate data type when you get the info out of storage.
You'll also be limited to storing 5 megs of data (I believe that is standard) but you probably have other issues if your form requires that much info. :)
Check these out for more info
http://msdn.microsoft.com/en-us/library/bg142799(v=vs.85).aspx
http://dev.w3.org/html5/webstorage/

You could use a POST instead of GET if you're only concern with the GET is the user seeing lengthy querystrings.

Use localStorage. localStorage lets you store values in the browser.

Get parameter from another page using javascript?

I have a wordpress site, and i'm not a php developer and not very eager to start either so I'm avoiding it like the plague, but I do have a requirement that requires a little bit of extra coding. I need to:
go to a different website,
download that page,
check for a certain phrase,
if phrase exists, extract a link from that page
and if link is returned I need to show that link on my wordpress site.
Currently, I have an asp.net page that does this and i'm hosting that page in an iframe on my wordpress site. but i'd like to do it without an iframe.
Question is, is there anyway for javascript to go to a different page (my asp.net page) and get a parameter (link) from it. If link is provided i will show certain content on wordpress site.
Or can javascript download a text file from the server? problem with that is i need a trigger to update the text file.
Any advice is appreciated.
Thanks.

What you should understand is that by "avoiding [PHP] like the plague" you're inadvertently avoiding the proper way of doing things. Javascript is a client-side language, and PHP is a server-side language. By asserting that you only want the load on the client's end (the kind of logic involved in what you want to do isn't exactly lightweight), you can potentially end up with a VERY slow webpage.
Not to mention, this type of situation is analogous to using a hammer to do a backhoe's job.
Either way, to answer your question, yes. You can use the jQuery Load method in tandem with Javascript's Match method.
What you should TRY to do, however, is make a CURL request using PHP, and then cache the page on your server. By doing this, you will limit the number of calls to a given page, and optimize load times.
Please consider the second option, even as an attempt in good practice. Good luck.

Use ajax and connect to a different page (on your server) which is written in server-sided language (like asp.net, as you said), that connects to the remote website.
More about Ajax

How can I scrape an ASP.NET site that does all interaction as postbacks?

Using Python, I built a scraper for an ASP.NET site (specifically a Jenzabar course searching portlet) that would create a new session, load the first search page, then simulate a search by posting back the required fields. However, something changed, and I can't figure out what, and now I get HTTP 500 responses to everything. There are no new fields in the browser's POST data that I can see.
I would ideally like to figure out how to fix my own scraper, but that is probably difficult to ask about on StackOverflow without including a ton of specific context, so I was wondering if there was a way to treat the page as a black box and just fire click events on the postback links I want, then get the HTML of the result.
I saw some answers on here about scraping with JavaScript, but they mostly seem to focus on waiting for javascript to load and then returning a normalized representation of the page. I want to simulate the browser actually clicking on the links and following the same path to execute the request.

Without knowing any specifics, my hunch is that you are using a hardcoded session id and the web server's app domain recycled and created new encryption/decryption keys, rendering your hardcoded session id (which was encrypted by the old keys) useless.

You could try using Firebugs NET tab to monitor all requests, browse around manually and then diff the requests that you generate with ones that your screen scraper is generating.

If you are just trying to simulate load, you might want to check out something like selenium, which runs through a browser and handles postbacks like a browser does.

Notify user on database change? JavaScript/AJAX

Yo.
I'm really quite new to this whole JavaScript business, not to mention AJAX, so I was thinking if you guys could help me out with a conundrum.
Basically, what I want is for the user to be notified upon a change in a value of a MySQL table. How should I go about that? Should I use jQuery, or can I slap something together myself?
Thankful for any and all replies.

Depending on how quickly you need the users to be notified, you could use either polling (sending a request every X seconds to see if there's anything new) or use comet.
In any case, you'll need a server side programming language to be querying the database and serving the results, and you'll need some javascript on the client-side to be sending requests and displaying responses. I would highly recommend using the jQuery library, since it simplifies a lot of cross-browser incompatibility.

Well, this is a bit abstract, but there are two parts to this: a server-side script, and your AJAX code (which sends this request to the script). Your server-side script will actually be doing the query to see if the database has changed, so your JavaScript will have to have a periodic execution (say once every ten seconds or whatever interval is right for you) if you are not waiting for the user to refresh their page.
The chain of events will look something like this:
AJAX -> Script -> DB -> Script -> AJAX -> Update Web Page
You will definitely want to use jQuery, Prototype, or some similar framework if you are new to AJAX. It will save you tons of time.

You should use jQuery and jQuery ajax method http://api.jquery.com/jQuery.ajax/

In the HTML page, the JavaScript will use AJAX to keep requesting a backend page during a certain interval.
The backend page will check if a MySQL database was changed.