Any bicyclic compound has two bridgeheads (shared by both rings) and three bridges.
The bicycloalkane is named by the total number of atoms in the two ring system - here 7 carbons, so "bicycloheptane".
The lengths of the three bridges are indicated using the brackets - here two 2 carbon bridges and one 1 carbon bridge so [2.2.1] The choice of a period over a comma was relatively arbitrary - but note that numbers separated by commas usually indicate locations of substituents.
The "endo" tells you that the OH is on the opposite side (trans) from the smaller (1 carbon) bridge. If you make a model, you will see that this is the more "interior" looking position compared to the position cis to the 1 carbon bridge, which is called "exo".
Numbering usually starts at a bridgehead then goes around the biggest bridge then the second then the smallest.
Well, you asked!
If you want a quick review of basic organic topics check out the book by Jakob Fredlos.