A digital currency is a form of currency that exists only in digital form, not as physical money. Cryptocurrencies use cryptography for security and many use blockchain technology. There are thousands of cryptocurrencies today with a total market value over $200 billion, though Bitcoin represents over 50% of that value. Cryptocurrencies allow direct transfers between parties without third parties like banks but their value fluctuates widely.

2. A digital currency is a form
of currency that is available
only in digital or electronic
form, and not in physical
form. It is also called digital
money, electronic money,
electronic currency
• Digital currencies are
intangible and can only be
owned and transacted in by
using computers or
electronic wallets which are
connected to the Internet or
the designated networks.

3. • A cryptocurrency is a digital or virtual currency that uses
cryptography for security. A cryptocurrency is difficult to
counterfeit because of this security feature. Many
cryptocurrencies are decentralized systems based on
blockchain technology.
• Today, there are literally thousands of cryptocurrencies in
existence, with an aggregate market value of over $200 billion
(Bitcoin currently represents more than 50% of the total
value).
•
•

4. • Cryptocurrencies hold the promise of making it easier to transfer funds
directly between two parties in a transaction, without the need for a
trusted third party such as a bank or credit card company
•
• fluctuate widely
 The semi-anonymous nature of cryptocurrency transactions makes them
well-suited for a host of nefarious activities, such as money laundering
and tax evasion
R(. However, cryptocurrency advocates often value the anonymity highly.
Some cryptocurrencies are more private than others. Bitcoin, for instance,
is a relatively poor choice for conducting illegal business online, and
forensic analysis of bitcoin transactions has led authorities to arrest and
prosecute criminals. More privacy-oriented coins do exist, such
DashZ,cashor or Monero)
•

5. 1. Ethereum
2. Bitcoin Cash
3. Litecoin
4. Dash
5. Bitcoin

6. • A blockchain is a digitized, decentralized, public ledger of all
cryptocurrency transactions. Constantly growing as ‘completed’ blocks
(the most recent transactions) are recorded and added to it in
chronological order, it allows market participants to keep track of
digital currency transactions without central recordkeeping.
• Any transactions in blockchain must be approved by all users:

8. • Every block has 3 elements (database-hashing-previous hashing)
• Hashing: is a function that converts an input of letters and
numbers into an encrypted output of a fixed length. A hash is
created using an algorithm, and is essential to blockchain
management in cryptocurrency.

9. • Every transaction has a special (maybe one block has more than 2500
transactions), moreover one block has one hashing!!!!!!!!
• In order to solve the huge number of hashing, blockchain developers
have designed Merkle Tree(A Merkle tree is a data structure that is
used in computer science applications. In bitcoin and other
cryptocurrencies​, Merkle trees serve to encode blockchain data more
efficiently and securely)

12. The hashes on the bottom row are referred to as "leaves,"
the intermediate hashes as "branches," and the hash at the
top as the "root.
HTC launches its blockchain-focused phone, but you
can only buy it in cryptocurrency
It is available for pre-order at a price of 0.15 bitcoins or
4.78 ether tokens, which translates to about $960, and is
expected to be shipped by December.

13. Bitcoin is a consensus
network that enables a
new payment system and
a completely digital
money. It is the first
decentralized peer-to-
peer payment network
that is powered by its
users with no central
authority or middlemen.

14. • Bitcoin is the first implementation of a concept called
"cryptocurrency", which was first described in 1998 by Wei
Dai on the cypherpunks mailing list, suggesting the idea of a
new form of money that uses cryptography to control its
creation and transactions, rather than a central authority.
The first Bitcoin specification and proof of concept was
published in 2009 in a cryptography mailing list by Satoshi
Nakamoto. Satoshi left the project in late 2010 without
revealing much about himself

15. What is the value of a bitcoin in us dollars
over the history of bitcoin !?
•

16. • Bitcoin’s transaction speeds are very slow at around 7
transactions per second. As a comparison, Visa performs around
24,000 transactions per second. In 2017 it was clear that there are
already too many transactions to handle and some reform is
required in order to allow Bitcoin to scale further.
• in August 2017 Bitcoin was basically split using a process called
“Hard Fork”, which created a new version of Bitcoin called
Bitcoin Cash. Bitcoin Cash uses the same codebase, but with a
Blocksize limit of 8Mb. This increased limit makes possible a
performance of around two million transactions processed per
day.
• You have take into account that Bitcoin cash = today 438.44$
• So the critical difference between both is Bithcoin cash has a
advantage in making more transactions per day rather than
Bitcoin.

17. -
I. Unconfirmed transactions aren't secure
II. Dencetralization (P2P)
III. No fees in transactions or minimum fees
IV. Able to buy online from huge companies ( Microsoft-
expedia-subway…etc)
V. Tomorrow my be millionaire
VI. All users record all daily transactions as much as
possible

18. • it consume so much energy
• If you forget your password, that’s mean , loss the money,
Bitcoin is not responsible for resetting password.
• Bitcoin price is volatile
• Bitcoin user is anonymous
• Illegal activities(The anonymous nature of bitcoin can’t go
without misuse. Bitcoin could be used for money laundering,
weapons and drug buying/selling… There is probably no way to
stop all of this from happening)
• Still few companies accept bitcoin as way of payment.

19. • Bitcoin mining is the process by which transactions are
verified and added to the public ledger, known as the block chain,
and also the means through which new bitcoin are released.
Anyone with access to the internet and suitable hardware can
participate in mining. The mining process involves compiling
recent transactions into blocks and trying to solve a
computationally difficult puzzle. The participant who first solves
the puzzle gets to place the next block on the block chain and
claim the rewards. The rewards, which incentivize mining, are
both the transaction fees associated with the transactions
compiled in the block as well as newly released bitcoin(you have
to know that the process doesn’t with your computer, some people
thought that obtain one bitcoin from laptop or computer maybe
take over 300000 years so you could not solve the algorithms.
•

20. • Choose a cloud mining service
provider. Over time, the
process of mining Bitcoin
requires more and more
processing power. Today, it is
impractical for many users to
invest in the equipment needed
to mine Bitcoin personally.
Cloud mining allows users to
rent processing (or hashing
power) power to mine Bitcoin
remotely.Bitcoin

21. •
• Purchase custom mining
hardware. When Bitcoin first
started, it was possible to mine
using only your desktop's CPU
and GPU. Today, that is nearly
impossible. You will be spending
far more on electricity than you
will earn mining coins. As Bitcoin
mining difficulty increases, more
and more powerful hardware is
needed to mine Bitcoin. As of
2018, you will need to purchase
an Application-specific integrated
circuit (ASIC) miner to mine
Bitcoin. There are a variety of
sources where you can buy ASIC
miners.[1] Here are some things
to consider when purchasing a
Bitcoin miner

22. • Bitcoin is unique in that only 21 million bitcoins will ever be
created, 80% produced, just we are mining for 20 %.
• Bitcion may finite at 2040.

23. • Bitcoin has never been fruad for many reasons, before mention
• Its, we have to define the meaning of fruad (wrongful or
criminal deception intended to result in financial or personal
gain)
oIn the site of Bitcoin, Specifically in read more before get
bitcoin, they are talking about the advantage and disadvantage
of its’.
oSince these informations are mentioned , the user is well
informed about the conditions and terms of bitcoin.
So, please if you want to get bitcoin from the site, you have to
read the condition very well before mining.

24. • several companies and websites accept bitcoin as means of
payment
So the currency is stilling in the process of developing by the way, nobody can
say whether Bitcoins will be worth more tomorrow than they are today, nor
can they give you any concrete answer as to whether you’ll receive a return on
your investment.