Explain the difference between helper and library in CodeIgniter.

Answer»

Helper	Library
Helper is a COLLECTION of common functions which we can use within Models, Views as well as in Controllers. Once we include the helper FILE, we can get access to the functions.	Library is a class that has a set of functions that permits for creating an instance of that class by $this->load->library() function.
It is not WRITTEN in object-oriented format.	It is written in an object-oriented format.
It can be CALLED in the same manner you call PHP functions.	You must create an object of the class to call library functions by using the $this->library_name->method().
All built-in helper file names are suffixed with a word _helper (ex: email_helper.php).	All built-in library files do not have a SPECIFIC suffix.

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