how includes work in php code example

Example 1: php check if string contains word

$myString = 'Hello Bob how are you?';
if (strpos($myString, 'Bob') !== false) {
    echo "My string contains Bob";
}

Example 2: str_includes php

<?php
$string = 'The lazy fox jumped over the fence';

if (str_contains($string, '')) {
    echo "Checking the existence of an empty string will always return true";
}

if (str_contains($string, 'lazy')) {
    echo "The string 'lazy' was found in the string\n";
}

if (str_contains($string, 'Lazy')) {
    echo 'The string "Lazy" was found in the string';
} else {
    echo '"Lazy" was not found because the case does not match';
}

# Checking the existence of the empty string will always return true
# The string 'lazy' was found in the string
# "Lazy" was not found because the case does not match