gitk is a command that is used for visualizing the commit graph and displaying all the history of the commits made and the information of files in the trees of each revision made. gitk is a very powerful GUI tool which is very handy to the command line ignorant.   To get started with gitk, we need to install it first. For Ubuntu users, follow the commands given below.

sudo apt-get update
sudo apt-get install gitk
To get installed in Mac, follow these commands.
brew doctor
brew update
brew install git
which git
  To bring up the gitk interface, run the command.
Here is a sample gitk interface.   The entire history of commits is shown in the GUI interface. The current head, the local branches, the commit message and who committed the messages are displayed. We can see the date and who committed the changes. Also, the files changed can be viewed.   gitk is very helpful for beginners who are not used to command line interface.]]>