Equal amounts of matter and antimatter should have been created in the Big Bang, yet the universe appears to contain very little antimatter today.
What happened to antimatter? Antihydrogen can be synthesised and trapped at low temperature which makes it possible to compare properties with its matter counterpart, hydrogen. Due to symmetry we expect them to be identical, but even a tiny difference might help solving the puzzle. In this talk I will show how antihydrogen is made and trapped in the ALPHA experiment at CERN together with our latest results on measurements of the spectrum, charge, and gravitational properties of antihydrogen.