Need help with drop box

[amlittlebit]

   I'm slowly starting to learn things here and appreciate everyone's help. I have a long way to go before I come close to some of you people. 
Will someone please explain this puzzle box to me, and what the drop box is? Usually you just have to retype the word or words in the box, but this often has a puzzle.
And what's the drop box thingie? 
Thank you!

[dcrotteau]

This is from the Drop Box web site: Dropbox is a free service that lets you bring all your photos, docs, and videos anywhere. This means that any file you save to your Dropbox will automatically save to all your computers, phones and even the Dropbox website.

Dropbox also makes it super easy to share with others, whether you're a student or professional, parent or grandparent. Even if you accidentally spill a latte on your laptop, have no fear! You can relax knowing that Dropbox always has you covered, and none of your stuff will ever be lost.

It's easy to use and there is a tour you can take that explains it all.

Good luck with it!