Selenium Webdriver submit() vs click()
The submit() function is there to make life easier. You can use it on any element inside of form tags to submit that form.
You can also search for the submit button and use click().
So the only difference is click() has to be done on the submit button and submit() can be done on any form element.
It's up to you.
http://docs.seleniumhq.org/docs/03_webdriver.jsp#user-input-filling-in-forms
There is a difference between click() and submit().
submit() submits the form and executes the URL that is given by the "action" attribute. If you have any javascript-function or jquery-plugin running to submit the form e.g. via ajax, submit() will ignore it. With click() the javascript-functions will be executed.
I was a great fan of submit() but not anymore.
In the web page that I test, I enter username and password and click Login. When I invoked usernametextbox.submit(), password textbox is cleared (becomes empty) and login keeps failing.
After breaking my head for sometime, when I replaced usernametextbox.submit() with loginbutton.click(), it worked like a magic.