C++: What is std::chrono?

1#include <chrono>
2using namespace std::chrono;
3
4// Durations
5auto sec = seconds(5);
6auto ms = milliseconds(100);
7auto min = minutes(2);
8
9// Clocks
10auto start = high_resolution_clock::now();
11// ... work ...
12auto end = high_resolution_clock::now();
13auto duration = duration_cast<milliseconds>(end - start);
14
15// Time points
16system_clock::time_point now = system_clock::now();
17system_clock::time_point tomorrow = now + hours(24);