How is the array function used in PHP?

In PHP, the array() function is used to create an array. Its usage can vary depending on the parameters passed to it.

1. Create an empty array.
2. Create an empty array named $arr.
3. Create an array that contains the specified elements.
4. Create an array called $arr with the elements element1, element2, and so on.
5. Create an array with specified keys and values using an associative array.
6. $arr is an array containing pairs of keys and values, with the format key1 => value1, key2 => value2, and so on.
7. Create an integer array by specifying the range.
8. Create an array with a range of numbers starting from a specified value, ending at another value, and with a specified step size.
9. Create an array using duplicate values.
10. Create an array with a specified number of elements starting from a specified index, all filled with the same value.
11. Create an associative array using key-value pairs.
12. Create an array by combining keys with values.
13. Merge multiple arrays into one array.
14. Combine all the arrays into one array.

The above are just some common uses of the array() function, there are other uses depending on specific requirements.