Creating PHP File for Repeated Content
I'm not sure if this is where I should put it as I'm just new here. But I just want to know if it is possible to create a .php file for the repeated content? An example would be, if I want to change the promo date of a certain coupon in the index and would like that change to take effect to all of the pages of the website by only editing the index page, how can I do it? Is it possible to do it in a .php file?
What I want is to lessen the time of editing each page and just edit the .php file instead of going through all of the 50+ pages of the website.
If this is possible, how can I do that and which particular code should I use?
I hope this question makes sense. :)
I really need help on this matter so any suggestions would be greatly appreciated.