I have a task: I have a log in box with username and password. And if combination of the email and user is incorrect when click the button log in to display text message "The email or password you entered is incorrect." with only jQuery. What do you think is it possible to check something like this in html page with jQuery . I think I need dynamic page and database and I need to use something like PHP ? Thanks for the opinion!
Well you shouldn't ask for opinions here but anyway if your useres are saved in a, lets say mysql database, you need defenitly a server side language (php...). Javascript and jquery are client side languages. That would mean that you need to send every visitor a list of every user, to check for a correct login.
Yes, you need database for sure to validate that combination is wrong. for doing it you can simply use ajax call to send values to a PHP page which then validate it with database query and the return you tru or false based on that response you can show error message on your page.
You can take refrence rom here How to validate a username / password via JQuery / Ajax?
I think I need dynamic page and database and I need to use something like PHP ?
True if you want to validate the user's username and password server side. You would be able to partially use jQuery with an ajax request, but you would still need some response from the server (which you could use PHP for) and you would need some database for the server to query.
Another option is to use something like Firebase, which is a client-side data management service. You would then be able to query and validate user credentials all client-side, but it would likely be insecure and not recommended.
Their Documentation: https://www.firebase.com/docs/
Hope this helps!