How can you check if a string contains a specific content in PHP?

To check if a string contains a specific content in PHP, you can use the `strpos()` function which returns the position of the first occurrence of a substring in a string. If the substring is not found, `strpos()` returns `false`. You can use this function to check if a specific content exists within a string.

$string = "Hello, world!";
$specificContent = "world";

if(strpos($string, $specificContent) !== false){
    echo "The string contains the specific content.";
} else {
    echo "The string does not contain the specific content.";
}