How to merge videos in Ubuntu

How to install mkvmerge

Open terminal (Ctrl+Alt+T), and enter the following:

sudo sh -c 'echo "deb http://mkvtoolnix.download/ubuntu/ $(lsb_release -sc) main" >> /etc/apt/sources.list.d/bunkus.org.list'

wget -q -O - https://mkvtoolnix.download/gpg-pub-moritzbunkus.txt | sudo apt-key add -

sudo apt-get update

sudo apt-get install mkvtoolnix mkvtoolnix-gui

Merge using Command Line

mkvmerge -o output.mkv source_01.mp4 \+ source_02.mp4 \+ source_03.mp4