I need your help to write some code which would update my webpage with out opening the particular page and do the changes in it. For example if i have 30 different pages site and i just want to display a message in all the 30 pages without open and edit them. It's tedius to do that. I know there is a technique to do that but i don't know how to do that and what should i do for that.
please help me with this.