7
Earlier the web browsers were text-based while now a days graphical-based or voice- based web
browsers are also available. Following are the most common web browser available today:
Browser Vendor Internet Explorer Microsoft Google Chrome Google Mozilla Firefox Mozilla Netscape
Navigator Netscape Communications Corp. Opera Opera Software Safari Apple Sea Monkey Mozilla
Foundation K-meleon K-meleon
Architecture
There are a lot of web browsers available in the market. All of them interpret and display
information on the screen however their capabilities and structure varies depending upon implementation.
But the most basic component that all web browsers must exhibit is listed below:
Controller/Dispatcher Interpreter Client Programs
Controller works as a control unit in CPU. It takes input from the keyboard or mouse, interpret it
and make other services to work on the basis of input it receives.
Interpreter receives the information from the controller and executes the instruction line by line.
Some interpreters are mandatory while some are optional For example, HTML interpreter
program is mandatory and java interpreter is optional.
Client Program describes the specific protocol that will be used to access a particular service. Following
are the client programs that are commonly used:
HTTP
SMTP
FTP
NNTP
POP
18. (a) Explain the creation of tables in detail [10]
The HTML tables allow web authors to arrange data like text, images, links, other tables, etc. into
rows and columns of cells.
tr and td Tags
The HTML tables are created using the
<table>
tag in which the
<tr>
tag is used to create table
rows and
<td>
tag is used to create data cells.
Here
border
is an attribute of <table> tag and it is used to put a border across all the cells. If you
do not need a border then you can use border="0".
Table Heading
Table heading can be defined using
<th>
tag. This tag will be put to replace <td> tag, which is
used to represent actual data cell. Normally you will put your top row as table heading as shown below,
otherwise you can use <th> element in any row.
Example
<!DOCTYPE html>
<html>
<head>
<title>HTML Table Header</title>
</head>
<body>
<table border="1">
<tr>
<th>Name</th>