What is JavaScript?
JavaScript is scripting language which is interpreted by almost all the browser engines whenever the webpage is loaded. The behavior of JavaScript may differ from browser to browser because some of the older browser engines do not interpret JavaScript accurately and may cause problem while loading a webpage.
JavaScript was developed by Brendan Eich at NetScape. JavaScript was first introduced to the world in December 1995. JavaScript was initially launched by the name of LiveScript which was later changed to JavaScript.
JavaScript is often used for form validation in webpage. Form validation can also be done by using PHP, but then validation will happen on the server side and later client will receive the response. Thus, the execution time will be more and it will increase load on your server. However, in case of JavaScript, it will use the client’s machine power and execution will be much faster because there will be no client-server round trips for validation. But due to security reasons, it is extremely important that you must have both JavaScript as well as server side verification because a web user always has an option to disable JavaScript in browser settings.
You can also use JavaScript to manipulate the content of a webpage and it will make your page more responsive and attractive to the user.
