DaVinci Resolve is the world’s only solution that combines editing, color correction, visual effects, motion graphics and audio post production all in one software tool! Its elegant, modern interface is fast to learn and easy enough for new users, yet powerful for professionals. DaVinci Resolve lets you work faster and at a higher quality because you don’t have to learn multiple apps or switch software for different tasks. That means you can work with camera original quality images throughout the entire process. It’s like having your own post production studio in a single app! Best of all, by learning DaVinci Resolve, you’re learning how to use the exact same tools used by Hollywood professionals!

Free and Paid versions available:

https://www.blackmagicdesign.com/products/davinciresolve/

NOTE: This is a subsection of their main website. They sell professional level editing hardware and cameras, which are not necessary for the operation of the free version.

HandBrake is a tool for converting video from nearly any format to a selection of modern, widely supported codecs.

Reasons you’ll love HandBrake:

• Convert video from nearly any format
• Free and Open Source
• Multi-Platform (Windows, Mac and Linux)

Free version available:

https://handbrake.fr/

VLC is a free and open source cross-platform multimedia player and framework that plays most multimedia files as well as DVDs, Audio CDs, VCDs, and various streaming protocols.

Free version available:

https://www.videolan.org/

Convert videos and movies to any format

With a simple application like Digital Video Converter, any user can transcode any of his video files to a more compatible and suitable format, depending on the media player he is going to use. Digital Video Converter is a free video processing program, specifically designed to convert videos to many output formats.

The supported input formats for the application are the following: AVI, DIVX, XVID, MP4, MPG, WMV, ASF, MOV, etc... And the output formats are: AVI (DivX, XviD, MPEG-4, H264), MPEG (MPEG-1, MPEG-2, VCD, SVCD, DVD), WMV, QuickTime ( MOV ), FLV, iPod, PSP, 3GP, WAV, and MP3.

With this application, it is also possible to configure several of the video coding options, like it's output size, the frame rate, the codecs used for both the video and audio feed, etc. And all the latter, from the applications main window.

Free version available:

https://www.malavida.com/en/soft/digital-video-converter/

Avidemux is a free video editor designed for simple cutting, filtering and encoding tasks. 

It supports many file types, including AVI, DVD compatible MPEG files, MP4 and ASF, using a variety of codecs. Tasks can be automated using projects, job queue and powerful scripting capabilities.

Avidemux is available for Linux, BSD, Mac OS X and Microsoft Windows under the GNU GPL license. The program was written from scratch by Mean, but code from other people and projects has been used as well. Patches, translations and even bug reports are always welcome.

Free version available:

http://avidemux.sourceforge.net/

Kdenlive is a free and open-source video editing software based on the MLT Framework, KDE and Qt. The project was started by Jason Wood in 2002, and is now maintained by a small team of developers. With the release of Kdenlive 15.04.0 in 2015 it became part of the official KDE Projects. Wikipedia

Free version available:

https://kdenlive.org/en/