It's hard to understand complex licenses that is why all photos on Pexels are licensed under the Creative Commons Zero (CC0) license. This means the pictures are completely free to be used for any legal purpose.
Pexels Videos offers completely free videos. All videos are licensed under the Creative Commons Zero (CC0) license. This means you can edit or change the videos and use them free for personal and even for commercial projects. All without asking for permission or setting a link to the source.
The Free Music Archive is an interactive library of high-quality, legal audio downloads directed by WFMU, the most renowned freeform radio station in America. Radio has always offered the public free access to new music. The Free Music Archive is a continuation of that purpose, designed for the age of the internet. It was launched in 2009.