What is PHP
- PHP stands for PHP: Hypertext Preprocessor
- PHP is a server-side scripting language, like ASP
- PHP scripts are executed on the server
- PHP supports many databases (MySQL, Informix, Oracle, Sybase, Solid, PostgreSQL, Generic ODBC, etc.)
- PHP is an open source software (OSS)
- PHP is free to download and use
- PHP files may contain text, HTML tags and scripts
- PHP files are returned to the browser as plain HTML
- PHP files have a file extension of “.php”, “.php3”, or “.phtml”.
- The PHP code start with <? php and ends with ?>
- In PHP, we use // to make a single-line comment or /* and */ to make a large comment block.
- The concatenation operator is (.) a dot . can be used to concatenate strings or variables.
- PHP variables are case sensitive but the functions are not case sensitive.
| Operator | Description | Example |
|---|---|---|
| $i==$j | equal to | 5==8 returns false |
| $i===$j | Value and type both are equal | |
| != | not equal | 5!=8 returns true |
| !== | Value and type both are not equal | |
| <> | Not equal to | |
| > | is greater than | 5>8 returns false |
| < | is less than | 5<8 returns true |
| >= | is greater than or equal to | 5>=8 returns false |
| <= | is less than or equal to | 5<=8 returns true |