SVN trunk, branches and tags

Working with SVN is somewhat like growing a tree:

a tree has a trunk and some branches
branches grow from the trunk, and thinner branches grow from thicker branches
a tree can grow with a trunk and no branch (but not for long)
a tree with branches but no trunk looks more like a bundle of twigs fallen on the floor
if the trunk is sick, so are the branches and eventually, the whole tree can die
if a branch is sick, you can cut it, and another one may grow
if a branch grows too much, it may become too heavy for the trunk, and the tree will fall down
when you feel your tree, your trunk, or a branch is nice looking, you can take a picture of it to remember how nice it was that day

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