SVN Conventions

The conventional layout for a new SVN repo is to contain three directories: trunk, branches, and tags. There are standard ways to use each of these folders. Gavin Baumanis described this fairly succinctly here:

The trunk / branches / tags folders are a naming convention to assist
humans in managing their code.

...

The convention says;
Do all your work in a directory named "trunk".
Do anything that might
break the trunk in a branch (a sub-directory of
the "branches" directory) -
so as not to break the trunk with
experimental code.
Use the "tags"
directory for a snapshot in time of the trunk at a
particular revision -
(File releases / some other milestone you want
to track).