The MAINTAINER instruction is an informational instruction of a Dockerfile. This instruction capability enables the authors to set the details in an image. Docker does not place any restrictions on placing the MAINTAINER instruction in Dockerfile. However, it is strongly recommended that you place it after the FROM instruction.

The following is the syntax of the MAINTAINER instruction, where <author's detail> can be in any text. However, it is strongly recommended that you use the image, author's name, and e-mail address as shown in this code syntax:

MAINTAINER <author's detail> 

Here is an example of the MAINTAINER instruction with the author's name and e-mail address:

MAINTAINER Dr. Peter <[email protected]>