When managing projects, it is really very rare not to have schedule changes or delays. Have you ever had to make several last-minute schedule changes, and later down the road wished you could go back to check what the original schedule looked like? Guess what... We can make that happen with Baselines.
Baselines are captures of your Gantt chart's current state. This feature saves the information so that you can later load it over your current chart, and compare timelines in order to see exactly what's changed.
They are particularly helpful when managing large projects since it allows you to keep track of changes and understand how the project has changed, and which particular tasks and subtasks are to blame.