Question

All PHP constants start with $_?

Answer 1

PHP constants do not start with $_; they are defined using define() or the const keyword and do not have the $ prefix.

Step-by-step explanation:

The statement that all PHP constants start with $_ is not accurate. In PHP, constants are defined using the define() function or the const keyword, and they do not have a $ prefix. The $ prefix is used for variables. Constants can contain letters, numbers, and underscores, but they must start with a letter or an underscore. It's common to use uppercase letters for constant names to distinguish them from variables. An example of defining a constant in PHP would be define("CONSTANT_NAME", "value") or const CONSTANT_NAME = "value". These constants can then be used throughout the code without needing the $ prefix.