What is a database hold on a second.
Maybe you are a smarty pants and you know what a database is, but trust me, in this section you may
learn a thing or two that will surprise you.
So no matter what level of experience, just hang in there, promise we'll get to some really fun stuff.
You see.
I remember when I first learned about databases and Eskil, I couldn't understand how it was all connected
with other fields.
I would learn about web development or python or machine learning and had no idea how this school or
databases really related to those fields.
So I want us to always understand the big picture and connect the dots so that the things you learn
in this course, you understand why it is useful and how we can use what we learn to do.
Some really interesting things in the world of tech.
So what is a database?
A database is a collection of data and also a method for us to access and manipulate that data.
So let's think about the statement.
Data is everywhere, right?
Data is now the most valuable commodity in the world.
Companies that control data, companies that have a lot of data like Uber, like Alibaba, like Amazon,
like Facebook, like Google, are some of the most valuable companies in the world because they have
this data.
And every day in our world, we produce data.
Right.
Whether it's drones with footages or location data, mobile phone apps, maybe website and web pages,
even security cameras.
We even have autonomous cars.
All those things collect data.
And the crazy part is that it's estimated we produce 2.5 quintillion bytes of data every year.
And by the way, quintillion means this many zeros.
It's a lot of zeros.
More data is collected in the past two years than the entire human history.
So where does all this data go?
Does it just get stored in a notebook?
Does somebody with pen and paper write it down?
No.
Right.
And how can you really have that statement that more data has been generated in the last two years than
all of human history combined?
I mean, sure, there's more humans on Earth, but there's always been the same number of atoms in the
universe.
You can just create something out of nothing.
When we say that data is being created more and more, the idea is that we're capturing this data.
We're saving this data somewhere to be used in some way.
Data is something that we as humans create.
But without capturing that data or using it, it's completely useless.
We use oil to power cars, but if we don't extract that oil, if we don't use that oil, it's completely
useless.
So we need a way to capture this data.
And that's what databases do.
They capture this data for us so that we can use it.
And here's another crazy number, 40 for the digital universe.
That is, the data that we store is estimated to be about 44 zettabytes of data.
How many zeros?
Once again, lots and lots of zeros.
So all this data is being captured.
In a database without a database, we wouldn't be able to store this massive amount of data and more
importantly, we can do some useful things with this data.
All those things we saw like autonomous cars, Instagram, Facebook, Google, without data, none of
it would work.
So without a database, the ability to query a database, that is to ask database information about
its data, it would be impossible for us to do a lot of things.
But here is a secret.
We mentioned that a database is a collection of data, in a way, for us to access and manipulate that
data.
But the secret is that databases aren't anything special, they're just hardware and software, there's
just computers.
So a database, even though we always see this scary looking cylinders are just computers.
We see images like this all the time representing databases, but they're just computers, it's hardware
with software.
So that is hardware is the mechanical part and the software is the actual code on top that allows us
to collect and use the data really useful.
So in this course, what you'll see is that we do the first step, which is one, we install software
to turn our computer into a database so that we can all practice.
And two, we add data to this database that we create with this software, and then we're going to start
using it and analyzing it, because at the end of the day, a database is exactly this just a disk drive,
a way for us to store ones and zeros on a computer?
And the beautiful thing is that as long as we can install something, we have a computer, something
with memory that we can store memory in, and we have a machine, a computer, we can create a database
that is we can create a database, even on a mobile phone, on our desktops or on our laptops.
And that's what we're going to do in the course.
But when you see somebody having a database, that's all it means.
They have a computer somewhere in the world with software installed for it to store and manipulate that
data.
Let's take a break and I'll see you in the next video.