Install xChm Viewer to read the CHM file on Ubuntu
The CHM format is supported by Windows and you don't need to install anything more. But, if you use Linux (Ubuntu,..) operating system, you need to install a piece of software to read the CHM format:
xCHM is a software to read CHM formats. It suports Linux (Ubuntu,..) operating system.
Installing the xChm on Ubuntu (Linux) is very simple. You only need to open the Terminal window and execute an only command below:
sudo apt-get install xchm
After finishing the installation, you can open CHM files with the xChm: