PHP is a server-side scripting language designed for web development but also used as a general-purpose programming language.
Originally created by Rasmus Lerdorf in 1994, the PHP reference implementation is now produced by The PHP Group.
PHP originally stood for Personal Home Page, but it now stands for the recursive acronym PHP: Hypertext Preprocessor.
PHP code may be embedded into HTML code, or it can be used in combination with various web template systems, web content management systems, and web frameworks.
isset(): checks if a variable has a value including (False, 0, or empty string), but not NULL. Returns TRUE if var exists; FALSE otherwise.
empty(): function checks if the variable has an empty value empty string , 0, NULL ,or False. Returns FALSE if var has a non-empty and non-zero value."
Use of explode() and implode() function
explode(): Convert string to Array
implode(): Convert Array to string
PSRs are PHP Standards Recommendations that aim at standardizing common aspects of PHP Development.
An example of a PSR is PSR-4, This PSR describes a specification for autoloading classes from file paths
The SQL injection is a malicious code injection technique. It exploiting SQL vulnerabilities in Web applications
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