Backups of individual files is offered on our shared hosting / reseller hosting plans. This includes daily / weekly / monthly backups.
For other services, such as VPS or dedicated servers backups are not offered by default. On a VPS we provide the option for a remote backup service in my.interserver.net (under the backup section) which is a remote FTP service that support nfs/samba as well for a remote drive mount. For dedicated servers most choose a second harddrive for backups, or the remote backup service.