Does this block every directory with the name "mypics" or only the first one off the root directory? For example, would everything in www.example.com/firstdirectory/seconddirectory/mypics/ be blocked too? Or do I have to specifically add
The search engines will only block the example.com/mypics/ and will crawl example.com/anythinghere/mypics/.
If you want to block all directories that contain the letters "mypics" you need to use wildcards aka pattern matching. This is not officially part of the robots.xt protocol but it is supported by the big three search engines. Be careful some of the smaller crawlers do not support wildcards.