how to make boundingbox

Hi, I have question how to make bounding box ?
And what are these numbers:

[boundingbox]
2.5
11.37
3.76
0
-0.05
2.28

[boundingbox]
{Length (x axis)}
{Width (y axis)}
{Height (z axis)}
{x coordinate refpoint}
{y coordinate refpoint}
{z coordinate refpoint}

Thanks for fast help.