Question: I am using OSX 10.9.5

Whenever I open a terminal, it says something like:

```
Last login: Wed Jan 21 10:29:13 on ttys002
You have mail.

```

What mail is it talking about ? If I open the mail app, I have no new mail. This is a laptop, and I have not setup a mail server, so how do I find out why it is reporting I have mail ? And how do I get rid of the message ?

Answer: 
Well, you probably have mail. ;)

It talks about your local inbox. Use `mail` or `mutt` or `from` to see your local mails. I'm not sure what mail client is installed per default on OSX, but I would expect to find `mail` on pretty much any unix system.

OSX, at the end, is just another unix and unix is designed to be a multi-user system, i.e. multiple different persons can use the same system at the same time. - In the time unix was designed it was common to have one big server and people were using a [terminal](http://en.wikipedia.org/wiki/Computer_terminal) for logging in remotely.

Therefore they should be able to communicate with each other. - One way is using mail. You can send someone locally a mail by typing `mail otheruser` and read your own mail by typing `mail`.

Even if you are the only user on your computer, system daemons might send you some mails to inform you about what is going on. (They can be configured what to send.)
that'll be comsat or biff (or something like that)

it's talking about the system mail spool. try the command `mail` 
it should be possible to tell the mail app to access the system mail spool, but I don't know the details.