Are there any specific PHP functions or libraries that are recommended for implementing a search feature on a website?

To implement a search feature on a website using PHP, you can utilize the `preg_match` function to search for a specific pattern within a string. You can also use the `stripos` function to perform a case-insensitive search. Additionally, you may consider using the `explode` function to break a string into an array of substrings based on a specified delimiter.

// Example code snippet to implement a basic search feature using preg_match
$searchTerm = "keyword";
$stringToSearch = "This is a sample string containing the keyword to search for.";

if (preg_match("/\b$searchTerm\b/i", $stringToSearch)) {
    echo "Keyword found in the string.";
} else {
    echo "Keyword not found in the string.";
}