When should I include "../" in the path to an include or image? [duplicate]

Of course, there is a rule, imagine that you are declaring the path to the one.jpg image in the index.php file within the following structure:

-index.php
-imgs
    - one.jpg
    - two.jpg
    ...

For this case above you would use this:

imgs/one.jpg

Another case will be:

-views
    - index.php
-imgs
    - one.jpg
    - two.jpg

Now you would have to declare that you want to go back 1 level ( ../ ) in the folder hierarchy, where the starting point is index.php itself, thus:

../imgs/one.jpg

That is, with this "declaration" ( ../ ) you are at views and imgs level, then yes, you can enter imgs and complete the path with the image you want, and same goes for longer path:

-public
    -views
        - index.php
-assets
    -imgs
        - one.jpg
        - two.jpg

Here you would have to go back two levels in the structure so that you can "enter" the folder assets and have access to imgs and then to the image, ../../assets/imgs/one.jpg

All of these uses involve using the relative path , rather than < a href="http://www.coffeecup.com/help/articles/absolute-vs-relative-pathslinks/"> absolute path