Root folder question (file extension precedence)

One simple question that I have seen answered on here but cannot for the life of me find the answer too.

In the root folder of your site what file extension would take precedence if both were placed in the same root folder?

Is it index.html or index.php

Just so everyone is clear, what would happen if I typed my address in, which file would it choose to display first. www.mysite.com/index.html or www.mysite.com/index.php

 

Not to worry, I've found out by just having try.

html if you are woundering

 

You can set this up in htaccess if you want to change it.

DirectoryIndex index.php3