what does this do?

[tipota]

ok, i still have a lot to learn, so dont laugh at my ignorance. ive seen pictures of peoples engine with a bar going across the top of the engine to the upper strut mounts. recently, when taking apart an old car, i realized that those bolts on the side of the engine hold in the struts, and i never knew this before so i never questioned the bar. now i realize that that bar is a suspension component, and im just wondering what it is called and what it does.

[scheffler]

strut tower bars improve handling and increase rigidity

[tipota]

so does this mean that when u take a hard turn, the car will remain more even rather than one side going up and the other going down? or do you need a roll bar for this? or are they the same thing? im still learning a lot about suspension components