Change Apache Listening Port

How to change Apache Listening port?
As default apache port was 80 or 8080. If the port had been use by other program the apache could not be started.

To change the default port to desired port, open the apache configuration file.
By default the file located at:
C:\Program Files\Apache Software Foundation\Apache2.2\conf

Open httpd.conf

Then find "Listen" Change the default number to your prefered number.

Eg: Listen 1000