Most of the time I use
Avidemux. It's simple but powerful. If you choose this one, however, download from the SourceForge mirror; FossHub has been problematic in the past.
Another program is
Shotcut. It also has a lot of features. However, depending on what you plan to do, a combination of Avidemux and Shotcut might be a possibility to consider

Finally, there is
Kdenlive, which is the most advanced of the three. However, it is also the most complicated to use, and most users won't need all its features. Also, this one is mainly built for Linux; the Windows version can be unstable sometimes.