Notices, Warnings and Fatal errors are the types of errors in PHP

☛ Notices:

Notices represents non-critical errors, i.e. accessing a variable that has not yet been defined. By default, such errors are not displayed to the user at all but whenever required, you can change this default behavior.

☛ Warnings:

Warnings are more serious errors but they do not result in script termination. i.e calling include() a file which does not exist. By default, these errors are displayed to the user.

☛ Fatal errors:

Fatal errors are critical errors i.e. calling a non-existent function or class. These errors cause the immediate termination of the script.