Photoshop is the best known photo editing software for macOS, but it's far from the only option. There are also some brilliant, feature-packed photo editors for your Mac if you don't need the power of Adobe's industry-standard app.
Why do you need a photo editor?
Digital photography has come a very long way in a very short time. The pictures you can capture with a recent smartphone are amazing, with resolution, colours and low-light performance that would have seemed impossible a few years ago.