Your files will be automatically saved in your /home/ workspace for you, up to 3GBs of data.
In Jupyter Notebook Workspaces, it's a good idea to save your checkpoints before you close the tab. We try to autosave jupyter notebooks every 90 seconds. If you've made changes in the last 90 seconds, we recommend that you hit the save icon. Then we will automatically back it up for your next session.