^start of line
41:01:00the literal text 41:01:00 \d{5}a digit, repeated exactly 5 times
:the literal : (5810 / 728 / 3A16)
\d{1,4}a digit, repeated between 1 and 4 times
$end of line
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string