Emmet: Emmet is a pluged in for many popular text editors which increate the HTML and css workflow and gives some shorthand method.

Framework vs Libaries

Both framework and Libaries are pre-written code use to provide structure for developing a software.

Framework: Framework provide foundation and set of convention for building a entire application under some guidelines. In framework we don't get the power of calling any method in our code. Ex-django

Libaries: Libaries use to perform some specific task in out code, you are in full control when a call a method from a libaries. Ex-React

CDN(Content delivery Network or Content Distributed Network): CDN is group of graphically distributed and interconnected server. Main purpose is to delivering web Content more quickly and effciently. It also reduces the load time of the server.

Why React called as React?

React says react because of its feature of reacting to changes in the data and rendering the appropriate changes in the user interface.

CROSS-ORIGIN IN SCRIPT: Cross-Origin is a mechanism on a web pages to be requested from another domain outside their own domain.

React vs React DOM

React: React is just javascript code created by facebook engineer. It basically use createElement. Using React it is easier to manipulate the DOM tree using javascript.

React DOM: Once you create React Element using React now we want to Render it on the browser but browser don't understand react so here React DOM comes into the picture React DOM help to convert the React Element into HTML tag.

Development mode vs Production Mode:

Development Mode: In development mode, we can enable and utilize React developers tools.

Production Mode: In Production Mode, compression and minification of javascript and other resources happens to reduce the size of the code

Async vs Defer

Async: In Async while HTML code is parsing along with the browser start fetching script tag from the network asynchronously, when browser fetch the script tag then HTML parsing is pause and browser start executing script tag code when execution complete then again HTML parsing will resume. In async mode order of execution is not guaranteed.

Defer: In defer mode while HTML code is parsing along with in parallel browser start fetching script tag from the network asynchronously, but when browser fetch the script tag still HTML parsing executed until Parsing in not completed, and then only execution of script tag start. In defer mode Order of execution of code is always guaranteed.

React.CreateElement: It will create and react element and return a javascript object

React.Render(): It helps to convert the React Element into HTML like code so that browser will understand and put inside the root(place where whole React code render).