Morzila Company introduce their Web Browser on 13 years ago, it is a Open Source Web Browser with lots of customize options and very end easy action to use.
By more simplifying I could say this browser is based in C+, JavaScript, C, CSS, XUL, XBL programming languages.
In addition this Web Browser is available in Multi-Platform in Windows Linux and MAC which is a convenient one. Also the versatility.
I always prefer to use this Web Browser for Single Web Site Permission for Every Add one also for Master Key Password, which helps you to prevent your saved passwords from others which is missing on other web browsers like Safari and Windows Edge and Google Chrome.
Some of us also feed some good support from Mozilla About Firefox periodically and I must say this is one of the best web browser till the date I use.
Mozilla also take low resources like RAM and Disk Space compared to Google Chrome and Safari in reality.
I also recommend this Web Browser to all of us.