I am extremely happy that I am a part of this course at beginners level and must commend professor @stream4u for his explicit lecture. The homework task is follows: **(1) What Is Cryptocurrency and How You Would Like To See Cryptocurrency In The Feature?** OR **(2) What Is Bitcoin and what was the Aim Behind Bitcoin Invention? Is Cryptocurrency Good For A Business To accept As Payment? Why?** OR **(3) What Is Public Chain and What will be the Advantages and Disadvantages of Public Chain?** However, I will be attempting question 3: >What Is Public Chain and What will be the Advantages and Disadvantages of Public Chain?

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To be able to understand ***Public Chain*** it will be important or imperative to get a knowledge of what of what blockchain is all about hence, I want to first try to throw a little light on Blockchain ***What Blockchain Is*** Blockchain appear to convoluted, and it sure enough can be, but its most important concept is actually quite simple. A blockchain is a sort of database. In order to be able to comprehend blockchain, it helps to foremost understand what a database really is. A database is a set of information electronically stored on a computer system. data, or Information in databases is structured typically in the format of a table to allow for easier searching and filtering for explicit or definite information. What is the variation between using a spreadsheet to store information rather than a database? Spreadsheets are designed for just one person, or a small group of people, for storing and accessing limited volume or quantity of information. In contrast, a database is patterned to accommodate significantly larger volume or quantity of information that is quickly and easily accessible, filtered, and tampered with by any number of users at once. Large databases accomplish this by accommodating or housing data on servers made of powerful computers. These servers can at some point be built using hundreds or thousands of computers for the purpose having the computational power and storage capacity required for many users to gain or obtain access to the database simultaneously. Although a database or spreadsheet may be easy to get along with to any number of people, it is frequently owned by a business and handled with skill by a designated individual that has total control over how it functions and the data within it. Blockchain is a definite type of database. In view of the way it stores information, it varies from a typical database; data in blockchains are stored in blocks that are subsequently chained together. While new data comes in it is inputted into a fresh block and as soon as the block is filled with data it is chained onto the former block, which makes the data chained together in the order of chronology. ***What Is a Public Blockchain?*** A public blockchain is a decentralized platform that is easy to get along with by anyone. This means that, it required no permission thus, anyone can come in, write and read the information available on the platform. A blockchain is a dispensed ledger in which transaction data is bundled and stored in the form of blocks. Consequently, a blockchain is formed by the combination of these ***“blocks”***. The timestamp is a key factor that distinguishes one block from the other. Once checked and validity proven, data stored on the platform can’t be changed or manipulated in spite of being publicly available. A public blockchain make use of a consensus mechanism to check and prove the validity of transactions. The two public blockchains flag bearers, ***Bitcoin*** and ***Ethereum***, makes use of the Proof-of-Work (PoW) consensus algorithm. Compared to private networks, a public blockchain presents greater transparency and also is more decentralized owing to the fact that anyone can join and there is no single entity that controls the whole system. Unluckily, a large number of public blockchains also undergo low transaction speeds as well as other scalability related issues. In addition,when compared to a private blockchain, a public blockchain is with certain limitations to a few consensus algorithm. The similarity between public and private blockchain is that each node on their network has an exact duplicate of their ledger, their stored data is not subject to change and the both platforms depend on transaction validators. A public blockchain has no restrictions. Anyone that has an internet connection can access to the network and begin checking or proving the validity of blocks and sending transactions. In a common manner, such networks is lokely to present some kinda incentive for users who proves the validity of the blocks. In public blockchain architecture, one can download the protocol at any time, without the need of any permission from anyone. The public blockchains depicts the optimal model that makes the technology industry so profitable. Consequently, it’s totally decentralized, no sole organization dictates the behavior of the ecosystem. Whilst on the contrary, a private blockchain can be manipulated and altered by the owning organization. A public blockchain exceed the absolute requisite of a third party. The system has a flow of its own that exist and evolved within the confines of the ecosystem. To that effect, it can simply be said to be purely decentralized, self-governed or autonomous digital public ledger. ***Characteristics of Public Blockchain*** The following are some characteristics of public blockchain that obviously distinguish it from other types of blockchain; * Nodes can be download and add to the system by anyone. * Compared to private blockchain, it is a bit slower. * The technology is completely a decentralized one. * Each node is allowed access to read and write on the ledger * It presents anonymity. ***The Advantages of Public Blockchain*** * Immutability The public blockchain network is totally immutable. This implies that no one can manipulate or tamper with the system or even steal away the money. If there is an attempt of double spending, all the other nodes will decline the transaction. Consequently, cases such as tax fraud and numerous other problems is mitigated with this technology. * Truly Decentralized Structure The public blockchain network infrastructure is completely decentralized. Hence, every of the nodes in the system will have exact duplicate of the ledger. Additionally, with the use of the consensus algorithms they can efficiently update the ledger. Public blockchain presents a truly decentralized structure as there is no need for any central control authority. * Greater Transparency Public blockchains possess a frequently shared consensus among the users of the network. Transparency is the reason why is the public blockchain network better and considered the new monetizing system and no one has control over anything. * User Empowerment A copy blockchain can be downloaded by anyone with an internet connection and as such has complete authority to read or re-write it. This implies that the general people possess the control panel, not a malevolent corporation. ***The Disadvantages of Public Blockchain*** * Speed Speed is one of the most significant problems with some public blockchain. For instance,bitcoin as a public blockchain processes about 4.6 transactions per second whilst on the contrary companies such Visa can process up to 1700 transactions per second. * Consensus Mechanism Most public blockchain such as Bitcoin makes use of Proof of Work (PoW) consensus algorithm in which the participants need to solve a difficult mathematical conundrum to check or prove the validity of a transaction. It demands the consumption of a reasonable number of resources which is a costly affair. * In public blockchains, there isn't need to prove one's identity all that is required to become a part of the network is just to commit one's processing power. This is my entry, Professor @stream4u, thanks for reading through. Cc:. @awesononso @xkool24 @hisgeneral