1
00:00:01,980 --> 00:00:06,240
We've covered a lot of ground in this course but now where you're going to have some fun. Let's go on

2
00:00:06,240 --> 00:00:11,820
a field trip and actually look at the Bitcoin network at work so you can actually see how all the concepts

3
00:00:11,820 --> 00:00:14,420
we've been looking at actually work in reality.

4
00:00:14,580 --> 00:00:20,010
For doing this, we're gonna be using a block explorer. A block explorer is a type of tool that enables you

5
00:00:20,010 --> 00:00:25,140
to see the bitcoin blockchain, or whichever blockchain you're looking at. For instance, right now you're

6
00:00:25,140 --> 00:00:30,930
looking at a block explorer found at blockchain.com/explorer What you'll find is that this block

7
00:00:30,930 --> 00:00:35,300
explorer not only lets you look at Bitcoin, it lets you look at other block chains. Ethereum... Here's

8
00:00:35,310 --> 00:00:40,650
Bitcoin Cash and there are other block explores for different blockchains. For the purposes of this course,

9
00:00:40,710 --> 00:00:42,750
we're focusing on blockchain and bitcoin.

10
00:00:42,750 --> 00:00:48,240
So let's drill down on bitcoin. Key things I want to point out to you about this is that Bitcoin is a

11
00:00:48,240 --> 00:00:53,550
public blockchain. As a public blockchain, that means that the information that's recorded on the bitcoin

12
00:00:53,550 --> 00:00:56,450
blockchain is available for everyone to see.

13
00:00:56,460 --> 00:01:02,360
That's why we will now be able to use this block explorer to look into the bitcoin blockchain.

14
00:01:02,460 --> 00:01:07,200
Key thing I want to point out to you is that, while we're looking at this information on the blockchain.com

15
00:01:07,200 --> 00:01:12,930
block explorer,  you will also be able to see other block explorers. For instance, this is BTC.com

16
00:01:12,930 --> 00:01:18,930
which also has a block explorer. And you'll find that right now, BTC.com is listing the latest

17
00:01:18,930 --> 00:01:23,380
block as block number 574,143

18
00:01:23,490 --> 00:01:29,460
That's... Before that's 574,142... 574,141... you see they're chronologically ordered.

19
00:01:30,390 --> 00:01:33,600
and you find that you see here who the different miners are.

20
00:01:33,630 --> 00:01:36,100
This was mined by a mining pool called Dpool.

21
00:01:36,120 --> 00:01:39,620
This was mined by mining pool called AntPool, this was mined by BTC.com...

22
00:01:39,660 --> 00:01:45,810
This was mined by Dpool etc. and if we go back to blockchain.com/explorer you will find

23
00:01:45,870 --> 00:01:47,070
the same thing.

24
00:01:47,070 --> 00:01:49,670
The latest block is 574,143.

25
00:01:49,770 --> 00:01:51,260
Same one that we had here.

26
00:01:51,480 --> 00:01:55,980
And so on and so forth. You will find that the miners are the same ones that are listed here etc...

27
00:01:56,100 --> 00:01:59,630
We're looking at the same exact information.

28
00:01:59,670 --> 00:02:02,510
Now let me point out some key things while we're here.

29
00:02:02,550 --> 00:02:07,170
What's interesting about this is that the block explorer will let you know every single transaction

30
00:02:07,170 --> 00:02:12,540
that's been inside the bitcoin blockchain all the way back to the first bitcoin block on the bitcoin

31
00:02:12,540 --> 00:02:13,330
blockchain.

32
00:02:13,350 --> 00:02:14,880
So that's the genesis block.

33
00:02:15,030 --> 00:02:22,050
So if right now I were to go to say the bitcoin mainnet and I go here 0. I'll be able to do a search,

34
00:02:22,230 --> 00:02:24,560
and it will take me back to block height 0.

35
00:02:24,570 --> 00:02:26,340
This is the first block ever.

36
00:02:26,340 --> 00:02:26,920
Right?

37
00:02:26,940 --> 00:02:32,250
And you see here... This is the first block, it's got its own block hash, and the previous block was 0000000...

38
00:02:32,250 --> 00:02:34,260
because there was no block before that.

39
00:02:34,260 --> 00:02:34,560
Right?

40
00:02:35,130 --> 00:02:38,680
And this actually took place on January 3rd 2009.

41
00:02:38,700 --> 00:02:43,350
Remember, we were talking about the fact that if you go inside here and you look at it there's only one

42
00:02:43,350 --> 00:02:44,190
transaction.

43
00:02:44,190 --> 00:02:50,700
And if I go into that transaction I will find that message we spoke about, The Time 03, January 2009

44
00:02:50,970 --> 00:02:53,580
Chancellor on brink of second bailout for banks.

45
00:02:53,580 --> 00:02:58,590
You see? All this information is recorded on the bitcoin blockchain permanently and immutably.

46
00:02:59,070 --> 00:03:01,080
Let's go back again to the block explorer.

47
00:03:01,290 --> 00:03:05,790
And while I'm here I'm going to show you some key things here. 'Cause this is a really interesting site

48
00:03:05,790 --> 00:03:06,890
that you can focus on.

49
00:03:06,930 --> 00:03:11,780
You will find constantly updated information for example for the price of bitcoin right now.

50
00:03:11,790 --> 00:03:15,170
This is an average across the major exchanges.

51
00:03:15,210 --> 00:03:18,320
That is because Bitcoin doesn't have one price.

52
00:03:18,420 --> 00:03:21,140
It depends on what somebody is willing to pay for a bitcoin.

53
00:03:21,150 --> 00:03:27,900
And different exchanges have different prices for bitcoin and because bitcoin is traded globally, sometimes

54
00:03:27,900 --> 00:03:32,790
you will find that Bitcoin is trading at a higher price in a certain country and it may be cheaper in

55
00:03:32,790 --> 00:03:37,350
another country. Or you will find that even in the same country, different exchanges will have different

56
00:03:37,350 --> 00:03:38,570
prices for bitcoin.

57
00:03:38,580 --> 00:03:39,840
So there's a variation.

58
00:03:39,840 --> 00:03:44,580
What you have here is the average market price when you go across the major exchanges. You have other

59
00:03:44,580 --> 00:03:46,260
information, such as the hash rate.

60
00:03:46,380 --> 00:03:48,920
This is the measurement of the network's processing power.

61
00:03:48,990 --> 00:03:53,380
That is when you really look at, and I'm going to take you to BTC.com for a moment -

62
00:03:53,460 --> 00:03:58,320
This is the hash rate which is the processing power for these miners.

63
00:03:58,320 --> 00:04:03,870
So this mining pool has a hash rate of 7,827 Petahashes per

64
00:04:03,870 --> 00:04:10,200
second. F2Pool has 5,883.36 Petahashes per second.

65
00:04:10,200 --> 00:04:11,720
This is the hash rate.

66
00:04:11,850 --> 00:04:15,260
And as you can see, different miners have different hash rates.

67
00:04:15,360 --> 00:04:21,360
And as a result, some miners when they have a lot more hash rate are able to mine blocks more often than

68
00:04:21,450 --> 00:04:22,720
others.

69
00:04:22,740 --> 00:04:25,830
However there are no guarantees that you will get all the blocks.

70
00:04:25,830 --> 00:04:31,890
So as we mentioned here, the number one in hash rate, definitely is BTC.com and they've mined a lot

71
00:04:31,890 --> 00:04:35,340
of blocks but not always because it's a competition.

72
00:04:35,410 --> 00:04:39,060
What you find as many of the other mining pools sometimes win as well.

73
00:04:39,060 --> 00:04:42,630
And BTC.com is by no means always the winner.

74
00:04:42,630 --> 00:04:47,250
Often this moves around, Antpool is sometimes the winner, F2 is the winner.

75
00:04:47,250 --> 00:04:53,340
You have different because miners change hash rate. Miners join the network, miners leave the network,

76
00:04:53,550 --> 00:04:59,270
miners sometimes pull out of the Bitcoin network and actually start mining Bitcoin Cash,  etc. There's

77
00:04:59,280 --> 00:05:03,580
many variables that will affect the hash rate for the Bitcoin network.

78
00:05:03,590 --> 00:05:09,020
Let's go back to blockchain.com/explorer. Key things I also want to point out to you here (because

79
00:05:09,020 --> 00:05:15,560
it's a very valuable site) is you can go specifically to there's a tab called Data and inside it you

80
00:05:15,560 --> 00:05:17,420
will find a link that says Charts.

81
00:05:17,420 --> 00:05:22,970
This is a priceless page that I want you to go to and I encourage you to follow along with everything

82
00:05:22,970 --> 00:05:28,460
I'm doing to see it for yourself because once you're done with this field trip you will know more about

83
00:05:28,460 --> 00:05:34,250
how to use bitcoin and how to see information in bitcoin than 90 percent of the people out there. If

84
00:05:34,250 --> 00:05:39,980
you can really master this lesson, you'll be able to truly know what bitcoin is all about.

85
00:05:39,980 --> 00:05:41,360
So key things you'll see here...

86
00:05:41,360 --> 00:05:46,040
And this is constantly updated information because as I mentioned the bitcoin blockchain is a public

87
00:05:46,040 --> 00:05:52,510
blockchain and all this information as it grows - blockchain.com constantly updates their charts.

88
00:05:52,700 --> 00:05:55,760
So key things you'll find here... Some of the popular stats:

89
00:05:55,820 --> 00:06:01,650
Obviously the market price is one, the number of transactions per day is very important too. Another

90
00:06:01,670 --> 00:06:04,370
thing I want to point out to you, is what's known as the mempool.

91
00:06:04,370 --> 00:06:11,830
The mempool, or memory pool, is the size of the number of transactions waiting to be confirmed.

92
00:06:11,840 --> 00:06:15,020
They define it as the aggregate size of transactions waiting to be confirmed.

93
00:06:15,260 --> 00:06:17,540
Let me show you what that means.

94
00:06:17,570 --> 00:06:21,350
This is at number of unconfirmed transactions.

95
00:06:21,350 --> 00:06:28,300
This is a live updating list. What you see is all the transactions that are coming into the Bitcoin network.

96
00:06:28,310 --> 00:06:33,560
Let me go one step further and refresh...  What you find is that there are 175 transactions

97
00:06:33,560 --> 00:06:38,990
per second that are shown. My screen cannot show you 175 transactions per second

98
00:06:38,990 --> 00:06:43,740
being shown... In fact, what you're seeing here is my computer trying to catch up and keep up with it.

99
00:06:43,820 --> 00:06:48,920
There's just a massive number of transactions constantly coming into bitcoin and you can see every single

100
00:06:48,920 --> 00:06:51,950
one of these transactions. This one is 4 BTC,

101
00:06:51,980 --> 00:06:53,720
That one's 21 bitcoins.

102
00:06:53,780 --> 00:06:56,570
We're looking at these... 128 bitcoins!

103
00:06:56,630 --> 00:07:01,300
There's some really, really large transactions that are constantly moving through the bitcoin blockchain

104
00:07:01,330 --> 00:07:08,330
and you can see it all happening here. Now, as the miners are creating new blocks, what they are doing

105
00:07:08,330 --> 00:07:13,610
is they are all, each mining group actually has a memory pool of their own,  in which they collect these

106
00:07:13,640 --> 00:07:19,310
unconfirmed transactions and from these unconfirmed transactions they start assembling blocks and then

107
00:07:19,310 --> 00:07:24,020
they get into competition with the other miners trying to see who will be able to create the latest

108
00:07:24,020 --> 00:07:25,670
block to add to the bitcoin blockchain.

109
00:07:25,970 --> 00:07:32,840
So what you're seeing here is the live Bitcoin network working 24 hours a day,  7 days a week as new

110
00:07:32,840 --> 00:07:34,640
transactions make it into the network.

111
00:07:35,660 --> 00:07:36,970
So let's do something right now.

112
00:07:37,080 --> 00:07:40,940
I'm going to go back now to the blockchain.com/explorer site.

113
00:07:40,940 --> 00:07:47,510
Let me go back here again and what you will find is that you have here all the latest transactions... You

114
00:07:47,510 --> 00:07:51,020
see a number of transactions per block that are coming into these.

115
00:07:51,140 --> 00:07:56,630
But you can also drill down into individual transactions and this is important because say for example

116
00:07:56,630 --> 00:07:58,820
you do a transaction with someone else.

117
00:07:59,030 --> 00:08:02,480
And the other person says "no, that transaction never arrived."

118
00:08:02,660 --> 00:08:08,420
As long as you have the transaction you can actually see if it's been confirmed and added to the bitcoin

119
00:08:08,490 --> 00:08:13,430
blockchain. That is, there's no doubts. If in fact the transaction is confirmed, that means that it's already

120
00:08:13,430 --> 00:08:16,730
been added to the bitcoin blockchain, therefore the transaction happened.

121
00:08:16,730 --> 00:08:17,970
Let's do that right now.

122
00:08:18,020 --> 00:08:22,790
If I go here, and I'm going to look inside the Bitcoin Mainnet, and I'm gonna look for specific transaction.

123
00:08:25,000 --> 00:08:30,220
I can paste the transaction number inside the block explorer, and I can search for it. And the block explorer

124
00:08:30,220 --> 00:08:34,890
will look at the Bitcoin blockchain, and it will find that transaction and give me back the results.

125
00:08:34,930 --> 00:08:41,770
What I find is that this transaction was actually received on December 29, 2017 and it's definitely confirmed

126
00:08:41,770 --> 00:08:46,330
in fact there's been 72,648 blocks since then.

127
00:08:46,330 --> 00:08:50,230
You can see that because it was included in block

128
00:08:50,230 --> 00:08:51,090
501,497

129
00:08:51,100 --> 00:08:55,060
Now the reason why I'm sharing this transaction with you is because I had already told you about this

130
00:08:55,060 --> 00:08:58,840
transaction. And it's a transaction where I hid a message inside.

131
00:08:58,840 --> 00:09:04,480
"We are changing the world one blockchain at a time", and that transaction is recorded permanently and

132
00:09:04,480 --> 00:09:05,440
immutably.

133
00:09:05,440 --> 00:09:10,690
Now here's what's interesting, this happened on December 29, 2017 in block

134
00:09:10,690 --> 00:09:12,130
501,497

135
00:09:12,130 --> 00:09:17,050
And yet when I come back, you will find that we're currently at block

136
00:09:17,050 --> 00:09:18,730
574,144.

137
00:09:18,730 --> 00:09:19,180
Interesting

138
00:09:19,180 --> 00:09:24,520
Key point is that, as you will notice, there has been a new block created since we last looked at this

139
00:09:24,520 --> 00:09:25,290
page.

140
00:09:25,390 --> 00:09:31,680
This latest blocks been created by AntPool and it contains 3,139 transactions.

141
00:09:31,720 --> 00:09:34,610
That block was mined four minutes ago.

142
00:09:34,750 --> 00:09:40,540
Now key things I want to point out to you from this whole perspective as well, is that all of this is

143
00:09:40,540 --> 00:09:44,050
happening 24 hours a day 7 days a week.

144
00:09:44,050 --> 00:09:49,240
And if you ever have any questions about any specific transaction you can simply do your search in here

145
00:09:50,720 --> 00:09:55,940
and one key thing that I want you to do while you're at it is make make sure to visit that link

146
00:09:55,940 --> 00:10:03,470
blockchain.com/btc/unconfirmed-transactions, because as you just heard - we just created

147
00:10:03,470 --> 00:10:04,660
a brand new block.

148
00:10:04,850 --> 00:10:09,680
And that's because from this group of unconfirmed transactions a miner just created another brand new

149
00:10:09,680 --> 00:10:09,970
block.

150
00:10:09,980 --> 00:10:14,520
You see how that unconfirmed transactions number dropped? From 8,000 to 5,000?

151
00:10:14,630 --> 00:10:19,010
And that's because we just got a brand new block. You got back to back blocks in the time that we actually

152
00:10:19,010 --> 00:10:20,320
looked at this little sample.

153
00:10:20,360 --> 00:10:24,510
So it's a really exciting thing that I encourage you to do because this never stops.

154
00:10:24,530 --> 00:10:26,330
It goes on 24 hours a day. Actually...

155
00:10:26,360 --> 00:10:30,500
Let's take a look at what just happened by going back to the block explorer and let me just refresh make

156
00:10:30,500 --> 00:10:36,740
sure I got the latest information - and I find that the latest block right now is mined by BTC.TOP

157
00:10:37,180 --> 00:10:40,820
and is block number 574,145  with

158
00:10:40,820 --> 00:10:43,990
3,282 transactions. We just saw that happen.

159
00:10:44,000 --> 00:10:46,540
Let's go to BTC.com and see what they show...

160
00:10:46,640 --> 00:10:47,960
And if I go, that's correct.

161
00:10:47,960 --> 00:10:49,120
I see the same exact thing.

162
00:10:49,120 --> 00:10:51,680
574,145

163
00:10:51,680 --> 00:10:53,720
And here's your reward.

164
00:10:53,720 --> 00:10:55,860
And this is the latest block.

165
00:10:55,970 --> 00:11:02,780
So again go back to blockchain.com/btc/unconfirmed-transactions and

166
00:11:02,780 --> 00:11:07,030
blockchain.com/explorer and do your own field trip on the bitcoin blockchain.