I restart my computer pretty infrequently and everytime I do, I can't connect to various things. Inevitably I realize I didn't run ssh-add and after debugging,

I restart my computer pretty infrequently and everytime I do, I can't connect to various things. Inevitably I realize I didn't run ssh-add and after debugging, things work again once I have run this command. But I never really looked into the basics. Thanks to this article I realize why I need to do that every time. :)