chckSum is an easy tool to check whether the checksum of a downloaded file is the same as the checksum provided by the vendor.
Important
Make sure to make the file executable before attempting to run. To do this, run chmod +x chckSum in the directory chckSum is stored.
To run, simply type ./chckSum in the directory the script is stored.
To install, just download the file, if you want to run it system-wide then enter the folder with chckSum and do this command:
sudo cp ./chckSum /usr/bin/
After that, chckSum will be installed system-wide.
If you, for some reason, needed to store this file elsewhere, you can add chckSum as an alias in your ~/.zshrc or ~/.bashrc file.
Lets say you stored it in your documents folder. To set an alias for it, you would run the command:
echo "alias chcksum="sh ~/Documents/chckSum" >> ~/.zshrc
or
echo "alias chcksum="sh ~/Documents/chckSum" >> ~/.bashrc
depending on which shell you use. If you use a different shell, you know how to set an alias.