Hilti is a European Professional brand based out of Lichtenstein (small country on the edge of Switzerland, Germany, and Austria). Factories are found in Lichtenstein, Germany, Austria, Hungary, China, Mexico, USA, and India.
They are known to have very comfortable tools with great reliability. Several companies use them as rentals. They are more expensive than most brands, and do not have a large variety of tools (compared to Milwaukee, etc.).
Personally I prefer Makita corded tools, especially circular saws. Their cordless tools are also very well made. I only have Milwaukee tools because the M12 automotive tools are amazing and I got the M18 tools on clearance.
Currently there are only a few large corporations that own the majority of brands.
Dewalt and Porter Cable fall under Stanley/BD.
Bosch is on their own.
Emerson Electric owns the Ridgid industrial brand.
TTI owns Milwaukee, but licenses the Ridgid and Ryobi (green tools) names to sell cordless tools in the US.
APEX has been slowly consolidating all their hand tools into the Gearwrench name.
Many brands also do not produce all their products. Many cordless brands outsource their hand tool production to factories that are already producing the same tools for other brands.
This graphic does leave out some brands like Makita and Ryobi Group Japan (dark colored tools), who are their own entities.
I've come to follow 2 conflicting truths about the modern manufacturing world.
1) Everything is made in the same factories, they just change the name on the label before it leaves.
2) You get what you pay for.
This makes brand loyalty for anything (cars, tools, etc.) irrelevant. Find the features you need, and find someone who makes it well.