I see a lot of folks asking for the best web application frameworks for web development. My question is - do we really need to start with a web application framework? what's the pros and cons of having it? or in another way, what's the pros and cons of web development without a web application framework?
Any framework is there to save you time. It should let you write application code, rather than boilerplate code. A framework should let you do a lot of configuration, to get it to do the stuff you wont want to have to implement yourself.
So if you want to save time, use a framework - unless you have a really simple app to write. E.g. you don't need a framework for a website consisting of a few static pages and a contact form.
Assuming you are building a web app, then the primary advantage is that using a web framework will help you move faster. Or, to put it another way, if you decide to go from scratch, you will have to build everything from the ground up. Which is probably not practical unless you are doing it for learning.
One principal of software engineering is code reuse. Don't reinvent the wheel. People have solved common problems and done a good job of it -- leverage their work to make your life easier. If you find a problem, fix it and contribute back.
A Web Framework will certainly help you acccomplish your goals faster most of the times. Except if you are either creating a really easy site or a really complicated one.
If you are going to code a big project then you should think of developing such a framework on your own, you can add features you need and adjust it however you want. Certainly you wouldn't have to learn another framework from scratch.
Last but not least you can always expand it whereas other frameworks maybe be closed or stopped being developed.
But for most things a web framework that is already there is the best way to go.