What does "->" mean/refer to in PHP?

It's like the period (.) in JavaScript and Java. It is just a simple access operator.

-> accesses a member of an object. So $wp_query->max_num_pages is accessing the field max_num_pages in the object $wp_query. It can be used to access either a method or a field belonging to an object, and if you're familiar with C++ or Java, it's equivalent to myObject.myField

Firstly you should understand the following. In PHP and many other languages we have the following types of entites:

• Variables
• Arrays
• Objects

The -> allows you to access a method or value within an object, the same way that [] allows you to access values within an array.

A class is like a box, and within that box there is a lot of items, and each item can interact with each other as they are within the same box.

For example:

class Box
{
    function firstItem()
    {

    }


    function secondItem()
    {

    }
}

The above is what we call a class. It's basically a structured piece of code that does not really do anything until it becomes an object.

The object is created by using the new keyword, which instantiates a class and creates an objects from it.

$box = new Box;

Now the above $box, which is an object created from the Box class, has methods inside, such as firstItem().

These are just like functions apart from within them we have another variable called $this and this is used to access other methods within that object.

Now to access the methods from outside the objects you have to use the operator described in your question.

$box->firstItem();

The operator -> will allow you to execute the method from the variable $box.