Photoshop is not the only photo editing tool on the market, but it is definitely a leader. Despite this, or because it has to be the best tool for so many people, it takes a very long time to start Photoshop on your computer.
On Windows, Photoshop SpeedUp is a freeware that can solve part of this issue. It gives all the tools to reduce load times for the big Adobe Photoshop tool.
Photoshop SpeedUP