$s = "PHP: Hypertext Preprocessor\n"
. "is a general-purpose programming language\n"
. "originally designed for web development";
$arr = array_filter(array_map('trim', explode("\n", $s)), 'strlen');
print_r($arr);
/*
run:
Array
(
[0] => PHP: Hypertext Preprocessor
[1] => is a general-purpose programming language
[2] => originally designed for web development
)
*/