Design Exploration > Using Checkpoints > About Checkpoints
  
About Checkpoints
Checkpoints represent stages in the design process. Each checkpoint captures incremental changes made to models in the active checkpoint. A new checkpoint is always added sequentially. When you add a new checkpoint, it is assigned a unique ID and default properties. You can modify properties of a checkpoint at any time.
You can activate a checkpoint at any time. When you return to a checkpoint, all open models are replaced in session with the versions from the active checkpoint.
All changes made to models in the Design Exploration session are saved to a checkpoint. When you use any type of Save command, a new checkpoint is added. Set the des_exp_confirm_on_save configuration option to no to disable conformation messages. You can update the last checkpoint in the tree or branch to save changes without adding a new checkpoint. To update an active checkpoint, that is not the last checkpoint in the tree or branch, you must first delete successor checkpoints.
Checkpoint Branches
Using checkpoint branches you can explore different design options. A branch can follow a specific design path. Then in a new branch you can try a different design path.
A new branch is created in the Checkpoint Tree when you add a checkpoint and the active checkpoint has one or more successor checkpoints. Branches are visible in the Checkpoints Tree when the Checkpoints Display is set to Tree.
When you are working in a branch, you can make this branch the main branch. Right-click the active checkpoint and select Make Active Branch Main. This branch becomes the main branch and checkpoints under the branch point become a branch.