In a word-processing program, select the track changes option under the review sub-menu. On clicking the track changes option, it gets enabled. Every change a user makes to the document is reflected in the document itself.
Explanation:
For instance, if a user tries to erase some content from the document, it will be struck-off in the selected color, which by default is red, and will still be visible rather than completely vanishing from the document.
Similarly, if the user tries to add some content it will be added in the same manner with the changed font color, and an underline just to reinforce the fact that it reflects a change made in the document.
