Variable Operations Operating on an initialized variable is 376% faster than operating on an unitialized variable. Constants are 146% slower than variables Local variables are 9.9% faster than global variables String Functions 'String' is 0.26% faster than "String" "String" is 4% faster than HEREDOC syntax "String\n" is 108% faster than 'String'."\n" 'String'.$var is 28% faster than "String$var" 'string '.$var.' string' is 55% faster than sprintf('string %s string', $var) "\n" is 70% faster than chr(10) strnatcmp() is 4.95% faster than strcmp() strcasecmp() is 45% faster than preg_match() strcasecmp() is 6.6% faster than strtoupper($string) == "STRING" strcasecmp() is 13% faster than strnatcasecmp() strtr($string, $string1, $string2) is 10% faster than str_replace() str_replace() is 161% faster than strtr($string, $array) stristr() is 10%...