What is the difference between uploaded datasets and managed datasets ?

There are three kinds of datasets in dataiku:

• Managed datasets: datasets that are created by recipe. Dataiku assumes he “owns” the data and schema of those datasets
• Uploaded datasets: raw files that are uploaded through the user interface. They are actually stored locally in raw form, in a specific folder (that you can find in DATA_DIR) with a subfolder per dataset name PROJECTNAME.DATASETNAME
  
  You can “modify” an uploaded dataset by reuploading it. An uploaded dataset is actually a folder, meaning that it can contain several files
• Non-managed, non-uploaded datasets. Usually it's a dataset that points to exisiting data (a table in a sql table for instance) that you can use as an input for a recipe