(DAS) is a block device from a disk which is physically [directly] attached to the host machine:
*You must place a filesystem upon it before it can be used.
*Technologies to do this include IDE, SCSI, SATA, etc.
(SAN) is a block device which is delivered over the network:
*Like DAS you must still place a filesystem upon it before it can used.
*Technologies to do this include FibreChannel, iSCSI, FoE, etc.
(NAS) is a filesystem delivered over the network:
*It is ready to mount and use.
*Technologies to do this include NFS, CIFS, AFS, etc.
![Photo: information about the storage technologies:
(DAS) is a block device from a disk which is physically [directly] attached to the host machine:
*You must place a filesystem upon it before it can be used.
*Technologies to do this include IDE, SCSI, SATA, etc.
(SAN) is a block device which is delivered over the network:
*Like DAS you must still place a filesystem upon it before it can used.
*Technologies to do this include FibreChannel, iSCSI, FoE, etc.
(NAS) is a filesystem delivered over the network:
*It is ready to mount and use.
*Technologies to do this include NFS, CIFS, AFS, etc.](https://m.ak.fbcdn.net/scontent-a.xx/hphotos-xpa1/v/t1.0-9/p526x296/559572_442627339119087_459039605_n.jpg?oh=bdaf91022cc1841e746b033b5fb63ee1&oe=544501D7)
*You must place a filesystem upon it before it can be used.
*Technologies to do this include IDE, SCSI, SATA, etc.
(SAN) is a block device which is delivered over the network:
*Like DAS you must still place a filesystem upon it before it can used.
*Technologies to do this include FibreChannel, iSCSI, FoE, etc.
(NAS) is a filesystem delivered over the network:
*It is ready to mount and use.
*Technologies to do this include NFS, CIFS, AFS, etc.