Space usage for the Computer Science system is divided into five catagories: home, projects, web, temporary, and semi-static.
In general, the department filesystem is centered around the concept of / (called "root") from our Linux filesystem. While many directories under / are local to each machine, a few are shared by all department workstations.
On Windows, \\cifs.cs.brown.edu\dfs corresponds to / on the Linux filesystem. By default, this is also mapped to Y: on department computers and Z: corresponds to your home directory (/home/username or \\cifs.cs.brown.edu\dfs\home\username).
See the Filesystem User Quotas page for filesystem layout and limitations on the amount of diskspace that will be provided for users. If you are working in the Sunlab, see the page on Identities, Quotas, and Limited Shell for more information on the space available for projects you work on there.
/contrib is a place for user-maintained programs and resources that everyone can use. If you're interested in maintaining software, use the /contrib/bin/contrib-req command to send a request to tstaff.
/data (backed up, but no .snapshots) and /nbu (not backed up and no .snapshots) are places for storage of large amounts of data or data important to more than one user. Most research data will go in /data, while large amounts of temporary data may go in /nbu. Email tstaff to request a personal or group directory on either of these filesystems.
As with /contrib and /data, the amount of space used is not limited, but we do ask that only files that are going to be available on the web be kept there.
There is a small amount of space available in /tmp on all machines. This space is not backed up and its files are removed by the system if the machine crashes or is rebooted. This space is available to all users, and is used automatically by many programs. You should not put your own files in here as it's a very temporary space and filling /tmp will usually cause a machine to crash.
There is a large amount of space available in each machine's /ltmp. This space is not backed up and the files do not go away when the machine is rebooted. They are removed, however, whenever a machine is reinstalled, but we try to give prior notice so anything in /ltmp can be moved to a safer place. Hard drives do fail; if you want to be especially cautious, it is suggested to not use /ltmp. This space is available to all users.