: Files with "MPL" in the name generally signal that the contents are under the Mozilla Public License , which allows you to use the code in larger works (even proprietary ones) as long as you keep the original MPL-covered files open and provide notice of changes. Quick Review: 7-Zip (.7z) Format
: It supports AES-256 encryption for both data and the archive structure (header encryption), making it a secure choice for sensitive storage. MPL.7z
If you are looking for a review of the archive format itself: : Files with "MPL" in the name generally