Override can substitute a file by another one in automatic way in Joomla . It can be used to complete an AllEvents displayed information for example..
This mini tutorial requests a limited knowledge of Joomla(developer).
How to proceed ?
You just have to simply add a file in your template and and consider the folders hierarchy.
We will use the so-called "protostar" template used for the website and not for the administration.
The themes of your website are located in the folder templates starting from the root (usually called www in you ftp tool.
Where locate my files ?
The override will be located in the folder templates/protostar/html.
In our example, we are going top override the webpage “event”. It’s located in the folder components/com_allevents/views/event/tmpl.
You just have to copy the files
from components/com_allevents/views/event/tmpl vers templates/protostar/html/com_allevents/event
The elements got back from the the tree are mentioned in blue and grey.
So, you have created your first override.