Why are file extensions case-sensitive on the web but not on localhost?

file, localhost, server-side, src

Solution

That depends on the operating system. Your server seems to run Linux which is normally case sensitive and if you run Windows on localhost it's not.

Problem

So I was trying to link an image on my website as `<img src="cat.png" alt="cat"/>` and for some reason it wasn't working. I later found out that when uploaded to my server the file was labeled as "cat.PNG" so I inputted that and it fixed. However, when I was testing my site on localhost, it was fine. Why is this? Is this some security issue or is localhost just smarter when it comes to parsing files? I know this is a weird and random question but I am curious. Thanks.

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