Block Diagram

1. Understanding the components of a web browser:-



Components of the web browser:-

(a) Layout Engine

The layout engine takes the input from the browser by means of URL bar, search box, mouse clicks and key presses thereby passing them to the rendering engine.

(b) Rendering Engine

The rendering engine takes HTML code and interprets it into what we see visually. For instance, a tag would be interpreted by the rendering engine as a set of instructions.

(c) User Interface

The user interface is the visual presentation of controls in the browser.

(d) Javascript Engine

The Javascript engine takes JavaScript code, parses it, executes it and returns the results.

(e) Network layer

The network layer is a function of the browser that happens behind the scenes and handles the network functions such as encryption, HTTP as well as FTP requests and all network settings such as timeouts and the handling of HTTP status codes.

(f) Storage

The storage includes cached files, cookies and recently browsers that have updated the ability to store data and objects created with JavaScript.

(g) Operating System Interface

The Operating System Interface provides the interaction between web browser and operating system.

2. Understanding the mechanism of how the web pages are displayed in the web browser:-


Step-by-Step Mechanism:
Step 1:- The web page is scripted and saved embedded with css and javascript.
While generating the web pages in web browser,
Step 2:- The web pages will be lexed, where it generates a list of tokens.
Step 3:- Then, it gets parsed.
Step 4:- The HTML interpreter will implement the Abstract Syntax Tree (Parse Tree), where it will call the Javascript loop.
Step 5:- The Javascript calls the write method, where the Javascript interpreter gets stored in the write method.
Step 6:- Then, the HTML interpreter will extract and write them, where it calls the graphics library (in-case if it's interactive texts or images or videos).
Step 7:- Finally, the web page is displayed in the web browser.