Data loader is a tool provided by the salesforce so that we can perform various functions through it. The functions could be insert, update, delete, export, export all, upsert. This is a migration tool which is used to migrate data more than 50,000 in number, but a drawback of it is that it cannot scheduled.
Thus to overcome this drawback we make use of dataloader through command line interface which is scheduled with task manager.
The most important part of setting up Salesforce Command Line Data loader is to generate the encrypted password using utility provided by the Data Loader.