how to

Figured this thread could be a handy resource for everyone at all skill-levels. Sometimes you just want to copy and paste a command you've used a hundred times (DD-tests, for example) or are just having a brain fart and forgot how to do something. Well... this thread is for you, my friend! Let's...

There are so many vps tutorial sites and I feel that most only have a little bit of content. The one I use most is Linode's library but was wondering if there was something that had a lot of content like Linode's but with different tutorials for different things. Any recommendations?