So let's look at some example, uh, DAPPs.
So I already mentioned the first DAPP,
the first example I wanna give you is a game,
and in fact, there are many games.
I kind of encourage you to look at, uh,
the site called DAPP Review that
looks at all sorts of DAPPs that have been posted out there,
all sorts of games and, uh,
various, um, of, uh,
of prediction markets and business logics that have been posted.
But this game is kind of incredible.
In that first of all, it's an extremely well-designed game,
uh, very very clever.
But to me, it's more than a game.
To me, it's basically a way to manage crypto assets.
It just so happens that the crypto asset is what's called a kitty.
Yeah. So what happens here is, uh, you,
um, send ether to,
uh, the cryptokitties game.
And as a result, uh, you basically, uh,
it's recorded that you own a particular cat.
Yeah. So this is what these cats look like.
Every cat is different,
you own your cat.
Uh, and you- you- remember the cat,
the cat now belongs to you,
and no one can take it away from you unless they have your secret key.
[NOISE] Yeah.
So there's a bit of a description here about the- how this kitty works- kitties work.
You can actually breed the kitty with other kitties.
Then you get offsprings and then you can sell the offsprings to other people.
In fact, um, when you buy these kitties you can kind of interact with other players.
So it's kind of a fun game to illustrate how crypto assets operate.
But again, it's an example of storing an asset on the blockchain.
In this case, it just happens to be a digital description of a cat.
Um, but it's there,
it's yours and no one can take it away from you.
And the interesting thing is, um, you know,
even if the company disappears,
even if cryptokitties as a company no longer exists, it doesn't matter.
The DAPP is on the blockchain.
The DAPP is gonna continue operating.
Your kitty belongs to you.
You can continue trading it using the blockchain and so on and so forth.
Yeah. So, um, uh,
[NOISE] this is kind of the beauty of these- of these DAPPs.
Even though if somebody wrote a code and they might disappear,
lose interest, it doesn't matter.
The code is posted on a blockchain and it's gonna run forever.
The other thing to rem- remember which I say again and again and again,
the data is public.
Which means that, um, in fact,
third parties can build on top of the game.
And in fact, there's a site called, uh,
KittyBattles where I could take the kitty that I
own and I can race it against the kitty that you own and see who wins.
There's a site called KittyHats where you can buy hats for your kitty.
Um, and those are separate DAPPs.
Yeah. So it's one DAPP that uses data that belongs to another DAPP.
But because the data is public,
there's nothing preventing one DAPP from in fact,
building on the data of another DAPP.
And so you can build these add-on products that,
uh, people might wanna buy in store.
And, again, once you buy a hat,
it's yours forever and no one can take it away from you.
So maybe this looks a little silly to you,
but once you play with it,
um, you re- you'll kind of realize,
you know, there's something different about playing these games than playing,
uh, like regular games on the- that're off the blockchain.
And just to show you that this thing is,
um, [NOISE] is real,
let me mention that when Cryptokitties launched,
there was a huge spike in the number of transactions in the ethereum blockchain.
As I said, this is implemented as a- as
a smart contract as a- as a DAPP on the ethereum blockchain.
We can see here, um, like,
uh, in the first couple of days that it launched,
there was massive massive, uh,
inve- investment from a lot of people in buying kitties.
So it's a game that people really kinda enjoy working, uh,
wor- playing with and,
um, and owning and intriguing.
And in fact, even when you look now there's constantly transactions, um,
happening on the, uh, on the ethereum blockchain related to- to crypto exchanges.
Yes. So in fact, as I said,
you can look at the sites DAPP Review and it'll show you
all the transactions that happen on a daily basis,
and there are many transactions on a daily basis related to cryptokitties.
Quite quite fascinating.
But there are lots of other examples of- of DAPPs that have been equally successful.
In fact, lots of business logic has been encoded as DAPPs.
Um, so, for example,
there are prediction markets.
Uh, like if you wanna, uh, uh, predict,
have a contract about the price of bitcoin relative to the price of ethereum,
you can have a contract about that.
Um, and uh, you know,
uh, basically transact with other people in that sense.
So Augur is a prediction markets DAPP devoted to this.
Uh, there are StableCoins implemented as a DAPP.
Um, so for example, pegged to the US dollar,
so you can look at some of how these StableCoins work.
[NOISE] And there are many many of these business logic applications encoded as DAPPs.
The question you always need to ask is why
do we put- why do we need to put this on the blockchain?
Is the blockchain the right, uh,
mechanism for, uh, the DAPP that I wanna build?
And so the- the- yeah, uh, you know,
in some cases the answer is no and in some cases the answer is yes.
Um, in particular, if you put- that-
if you do decide to put a DAPP on the blockchain, you know,
business logic on the block- on the blockchain,
what it means is that the business logic itself is enforced by the blockchain protocol.
So again, the miners are the ones that are enforcing the business logic.
So the rules in the code are followed correctly and they can never be changed.
And moreover, uh, you get transparency.
So in fact, there's no need to trust, uh, third parties.
Everyone can look on the blockchain and make sure that the rules are followed correctly.
Now, I should caveat this a little bit in that.
In fact, there is a mechanism by which you can change
the code if you decide that your old code needs to be updated.
In fact, there is a way that the owner can update the code that,
um, implements a particular DAPP.
But all of that is gonna be completely transparent.
So it'll show on the blockchain- blockchain that
the code was changed from one version to another version,
and both versions are gonna be available for the public to inspect.
So everything is transparent, everything is verifiable,
and the code has to be run the way
it was written that's basically enforced by the miners.
Okay. So that's kind of the- the interesting aspect
of putting business logic on the blockchain.