What is the logical structure of the disk resources? | Oracle DBA

Following is the logical structure of the disk resources:
 Data block — Refers to the smallest logical storage unit. Size of a data block is a multiple of operating system block size.
 Extent — Refers to the contiguous set of data blocks, which is allocated as a unit to a segment.
 Tablespace — Refers to the final logical storage unit. It is mapped to physical datafile.
 Segment— Allocates a logical structure, such as table. It is a set of extents, which are stored in the same
tablespace.