If a method can be static, declare it static.
Speed improvement is by a factor of 4
1. echo is better than print
echo( 'CHECKMATE: PLAY with PROBLEMS' );
// is better than
print( 'CHECKMATE: PLAY with PROBLEMS' );
2. Use echo' s multiple parameters instead of string concatenation
echo 'PLAY', 'WITH', 'PROBLEMS';
// is better than
echo 'PLAY' . 'WITH' . 'PROBLEMS';
3. Surrounding your string by ' instead of " will make things interpret a little faster since PHP looks
for variables inside "..." but not inside...