UOS Lahore Msc IT

1)Write HTML and CSS code for this 

2)Do following using JavaScript :

• Change text
• Change color
• Change class attributes

• Variable names are case-sensitive.
• A variable’s name can be any legal identifier.
• It can contain Unicode letter,Digits and Two Special Characters such as Underscore and dollar Sign.
• Length of Variable name can be any number.
• Its necessary to use Alphabet at the start (however we can use underscore , but do not use it )
• Some auto generated variables may contain ‘$‘ sign. But try to avoid using Dollar Sign.
• White space is not permitted.
• Special Characters are not allowed.
• Digit at start is not allowed
• Subsequent characters may be letters, digits, dollar signs, or underscore characters.
• Variable name must not be a keyword or reserved word.

Some Standard Conventions Used :

1. Never Use Dollar Or Underscore as First Letter

• Dollar Sign and Underscore as First Character in Variable name is allowed but still its not good programming Style to use it as First Character.
• Generally we use Underscore in “Constant Value” variable.

static final int TOTAL_NUM = 10;
static final int MAX_COUNT = 20;

2. Capitalization of First Character of Second Word

• If variable name contain two words then write first letter of second word in Capital Case.
• If variable name contain single word then write that word in small case.

Example : Multiple Words in Variable Name

sumOfNumber
firstNumber
skinColor

Example : Single Word in Variable Name

sum
first
last

Posted by : Abdul Razzaq

Primitive/Built in Data Types in Java:

Variables are nothing but reserved memory locations to store values. This means that

when you create a variable you reserve some space in memory.

Based on the data type of a variable, the operating system allocates memory and

decides what can be stored in the reserved memory. Therefore, by assigning different

data types to variables, you can store integers, decimals, or characters in these

variables.

There are two data types available in Java: