It is possible Laptop is also a system
But I would not recommend it to make a server
Laptops emit lots of heat and I would not recommend

Let's go with desktop before your laptop has gone. Remember that any personal server can be crash data. It happends with me one time.

Laptops make for ideal mobile servers if you need one on the go. Like the massive 21" 2 chip versions. Not cheap, but fun on the go servers.

There is no harm to configure your own laptop as webserver. Only you need to take precaution of your data. There should be backup configured for data stored on laptop.

possible, but BETTER if you use a proper computer,

You will need to turn it on always, laptop easily gets hot.

I don't think thats a good idea for any reason except for fun.

If you really have to, as in, you cant afford to purchase another pc, then yeah why not, just make sure you have it in a good place to keep it cool and/or get a cooling fan for laptops, i have one that works well to keep my laptop cool.

It is possible to run a web server on your laptop, but highly recommended that you do not if you are wanting to launch it as a production server.

I have in the past ran a web server on my laptop when I had been traveling without internet to keep up with development on a few websites.

If you are wanting some simple software to assist you in this, check out WAMP Server or xampp. They are great for quick setups and come with Apache, MySQL and PHP. They are only recommended for development servers though. They can be production server quality if they are configured correctly.

I think its possible but i cannot turn my laptop 24/7 for that. besides, it would be more of a hassle and you might want to have a shared plan for that.

you can use laptop for webserver but you want to have static ip and very good internet connection so it will work as you required

First off you want to define 'Webserver' - are you wanting to serve websites? FTP Dump? SNMP? What's it gonna do?

Then you can decide if it can be used or not

Yes, it's very possible. All you need to do is to install all the required softwares on your PC.But Cost effectiveness - what you would pay in terms of electricity and bandwidth (if your site has a lot of traffic).

It's not a good idea as it would run slow.