You want the samba server then.

I suggest you use the synaptic package manager to see what's what (I don't use synaptic but there are plenty of folk on this forum that do).

Search in synaptic for packages with names containing samba. You should find at least:

ii samba 2:3.5.6~dfsg-3 SMB/CIFS file, print, and login server for Unix
ii samba-common 2:3.5.6~dfsg-3 common files used by both the Samba server and client
ii samba-common-bin 2:3.5.6~dfsg-3 common files used by both the Samba server and client

I think the find the second two are already installed so the samba client will work out of the box. You'll need to install the first, the samba server. Once upon a time it might have been included by default but not any more.