The need for a database originates from the fact that computers are dumb devices having batman like abilities which can be smartly be utilised by feeding it the right content. That is, for example, consider any live scenario or apps that exist today be it WhatsApp, Facebook or be it a 200 user based financial domain website - without a good data content, it is simply a well-built skeleton only.
So now that we know about the importance of data comes the question of how to store the database. This very same question came in the 70s also to earlier developers and researchers - then there were some like E.F.Codd who came up with a blueprint or design for storing data. This included 12 rules to have an effective database design.
Will elaborate that in a different lesson and take up from there Thank you.