1.plug in- A software model you can install into a wordpress site, can be functional or utilitarian. There are many different types of plug on.
– add social media icons
-add carousel
2.The primary language of a plug in is going to be Php. The plug in may have its own CSS sheet or HTML sheet. Also has javascript.
3. Add calendars, light box plug-ins, shopping cart, security
4. Putting two plug-in’s by each other may cause a conflict. (Different versions of Javascript) The site could be locked, if the site locks completely,
5. Issues- publisher may not support it anymore
6. Update and back up to maintain site.