It is no surprise that attempts such as those of CODASYL and ANSI to develop data structure language (DDL) and data manipulation language (DML) in separate communities have yielded many misunderstandings and incompatibilities. E. F. Codd
Seeing the world differently is one of the toughest incompatibilities to reconcile in a relationship. Mariella Frostrup
Compatibility The USB standard specifies relatively loose tolerances for compliant USB connectors to minimize physical incompatibilities in connectors from different vendors. Source: Internet
As of the official 2.0.0 release on February 24, 2013, there were only five known (minor) incompatibilities. Source: Internet
In addition, there are many subtle, usually software-driven incompatibilities between the two. 5¼-inch disks formatted for use with Apple II computers would be unreadable and treated as unformatted on a Commodore. Source: Internet
Early PC/ATs were plagued with reliability problems, in part because of some software and hardware incompatibilities, but mostly related to the internal 20 MB hard disk, and High Density Floppy Disk Drive. Source: Internet