DB25 Connector - D Series Electrical Connector.
The DB25 Connector is used to connect up data communications equipment. This D-Subminature Connector is used on many systems to connect up both serial and parallel connections. The DB-25 Connector is a two row system with 13 and 12 Pins this forces connector to only insert in one way. The D-Series Connector was in introduced by Cannon Corporation in 1952 the Part Numbering uses the D as the prefix for the Series.DB25-Female Connector

The DB25-F on the Device is primarly used on the Parallel Interface one of the most popular implementation of this was on the IBM-PC Computer. The second most popular usage was for SCSI Interface. If you see one on a system or device it most likely is a Parallel Interface. Connecting the Parallel Port to the circuit Board.
1. Connect IDC-26 Conector to Main Circuit Board.
2. Route Cable to Panel.
2. Install DB-25 Female in Panel or Bracket.
DB25-Male Connector

Connecting a Serial Port to the Cicuit Board.
1. Connector the IDC-10 Connector to the Main Circuit Board. (Important pin-1 has a Red Wire on the Ribbon Cable).
2. Route the Cable to the Panel.
3. Install DB-25 Male in Panel or bracket.