HP would refer to Horsepower. This would refer to how strong the engine is. The BHP is known to be the input brake horsepower of the engine. This would help measure the engine’s power without different power losses. The HP, on the other hand, is known to be one of the quantities that can be used to describe power.
A lot of people think that these two terms should be interchanged anyway since there aren’t a lot of differences anyway. In fact, some people only use BHP when they want to be more specific but if not, they would rather use HP as this is a term that more people are familiar with.