LinkedIn is the largest business and employment-oriented social networking platform in the world and enables you to easily connect to opportunities and tap into your professional potentials. It also makes it easier for you to discover, connect and nurture relationships with important people, search and apply for good jobs, and get latest news of your followed topics and companies.

And the most important part of such social networking apps is the personal information that you have filled in the beginning. Hence, in this prototype, we have added many relevant pages that allow users to fill their personal information in details. And the flow and logic of these pages are also really worth learning, if you are trying to build such a great social networking app prototype.

A binary code represents text, computer processor instructions, or other data using any two-symbol system, but often the binary number system's 0 and 1. The binary code assigns a pattern of binary digits (bits) to each character, instruction, etc. For example, a binary string of eight bits can represent any of 256 possible values and can therefore represent a variety of different items.

In computing and telecommunications, binary codes are used for various methods of encoding data, such as character strings, into bit strings. Those methods may use fixed-width or variable-width strings. In a fixed-width binary code, each letter, digit, or other character is represented by a bit string of the same length; that bit string, interpreted as a binary number, is usually displayed in code tables in octal, decimal or hexadecimalnotation. There are many character sets and many character encodings for them.

A bit string, interpreted as a binary number, can be translated into a decimal number. For example, the lower case a, if represented by the bit string 01100001 (as it is in the standard ASCII code), can also be represented as the decimal number 97.

The modern binary number system, the basis for binary code, was invented by Gottfried Leibniz in 1679 and appears in his article Explication de l'Arithmétique Binaire. The full title is translated into English as the "Explanation of the binary arithmetic", which uses only the characters 1 and 0, with some remarks on its usefulness, and on the light it throws on the ancient Chinese figures of Fu Xi."^[1] (1703). Leibniz's system uses 0 and 1, like the modern binary numeral system. Leibniz encountered the I Ching through French Jesuit Joachim Bouvet and noted with fascination how its hexagramscorrespond to the binary numbers from 0 to 111111, and concluded that this mapping was evidence of major Chinese accomplishments in the sort of philosophical mathematics he admired.^[2][3] Leibniz saw the hexagrams as an affirmation of the universality of his own religious belief.^[3]

Binary numerals were central to Leibniz's theology. He believed that binary numbers were symbolic of the Christian idea of creatio ex nihilo or creation out of nothing.^[4] Leibniz was trying to find a system that converts logic’s verbal statements into a pure mathematical one. After his ideas were ignored, he came across a classic Chinese text called I Ching or ‘Book of Changes’, which used a type of binary code. The book had confirmed his theory that life could be simplified or reduced down to a series of straightforward propositions. He created a system consisting of rows of zeros and ones. During this time period, Leibniz had not yet found a use for this system.^[5]

Binary systems predating Leibniz also existed in the ancient world. The aforementioned I Ching that Leibniz encountered dates from the 9th century BC in China.^[6] The binary system of the I Ching, a text for divination, is based on the duality of yin and yang.^[7] Slit drums with binary tones are used to encode messages across Africa and Asia.^[7] The Indian scholar Pingala (around 5th–2nd centuries BC) developed a binary system for describing prosody in his Chandashutram.^[8][9]

George Boole

The residents of the island of Mangareva in French Polynesia were using a hybrid binary-decimal system before 1450.^[10] In the 11th century, scholar and philosopher Shao Yong developed a method for arranging the hexagrams which corresponds, albeit unintentionally, to the sequence 0 to 63, as represented in binary, with yin as 0, yang as 1 and the least significant bit on top. The ordering is also the lexicographical order on sextuples of elements chosen from a two-element set.^[11]

In 1605 Francis Bacon discussed a system whereby letters of the alphabet could be reduced to sequences of binary digits, which could then be encoded as scarcely visible variations in the font in any random text.^[12] Importantly for the general theory of binary encoding, he added that this method could be used with any objects at all: "provided those objects be capable of a twofold difference only; as by Bells, by Trumpets, by Lights and Torches, by the report of Muskets, and any instruments of like nature".^[12]

Another mathematician and philosopher by the name of George Boole published a paper in 1847 called 'The Mathematical Analysis of Logic' that describes an algebraic system of logic, now known as Boolean algebra. Boole’s system was based on binary, a yes-no, on-off approach that consisted of the three most basic operations: AND, OR, and NOT.^[13] This system was not put into use until a graduate student from Massachusetts Institute of Technology by the name of Claude Shannon noticed that the Boolean algebra he learned was similar to an electric circuit. Shannon wrote his thesis in 1937, which implemented his findings. Shannon's thesis became a starting point for the use of the binary code in practical applications such as computers, electric circuits, and more.^[14]

Li-Fi is a bidirectional, high-speed and fully networked wireless communication technology similar to Wi-Fi. The term was coined by Harald Haas^[1] and is a form of optical wireless communications (OWC) and uses the visible spectrum as well as ultraviolet and infrared radiation. Li-Fi could be a complement to RF communication (Wi-Fi or cellular networks), or even a replacement in contexts of data broadcasting. It is currently being developed by many organisations all over the world.

It is wire and UV visible-light communication or infrared and near-ultraviolet instead of radio-frequency spectrum, part of optical wireless communications technology, which carries much more information and has been proposed as a solution to the RF-bandwidth limitations.^[2]

This OWC technology uses light from light-emitting diodes (LEDs) as a medium to deliver networked, mobile, high-speed communication in a similar manner to Wi-Fi.^[3] The Li-Fi market is projected to have a compound annual growth rate of 82% from 2013 to 2018 and to be worth over $6 billion per year by 2018.^[4]

Visible light communications (VLC) works by switching the current to the LEDs off and on at a very high rate,^[5] too quick to be noticed by the human eye. Although Li-Fi LEDs would have to be kept on to transmit data, they could be dimmed to below human visibility while still emitting enough light to carry data.^[6] The light waves cannot penetrate walls which makes a much shorter range, though more secure from hacking, relative to Wi-Fi.^[7][8] Direct line of sight is not necessary for Li-Fi to transmit a signal; light reflected off the walls can achieve 70 Mbit/s.^[9][10]

Li-Fi has the advantage of being useful in electromagnetic sensitive areas such as in aircraft cabins, hospitals and nuclear power plants without causing electromagnetic interference.^[7][11][8] Both Wi-Fi and Li-Fi transmit data over the electromagnetic spectrum, but whereas Wi-Fi utilizes radio waves, Li-Fi uses visible light, Ultraviolet and Infrared. While the US Federal Communications Commission has warned of a potential spectrum crisis because Wi-Fi is close to full capacity, Li-Fi has almost no limitations on capacity.^[12]The visible light spectrum is 10,000 times larger than the entire radio frequency spectrum.^[13] Researchers have reached data rates of over 224 Gbit/s, which is much faster than typical fast broadband in 2013.^[14][15] Li-Fi is expected to be ten times cheaper than Wi-Fi.^[6] Short range, low reliability and high installation costs are the potential downsides.^[4][5]

PureLiFi demonstrated the first commercially available Li-Fi system, the Li-1st, at the 2014 Mobile World Congress in Barcelona.^[16]

Bg-Fi is a Li-Fi system consisting of an application for a mobile device, and a simple consumer product, like an IoT (Internet of Things) device, with color sensor, microcontroller, and embedded software. Light from the mobile device display communicates to the color sensor on the consumer product, which converts the light into digital information. Light emitting diodes enable the consumer product to communicate synchronously with the mobile device.^[17

Bitcoin is a cryptocurrency and worldwide payment system.^[8]:3 It is the first decentralized digital currency, as the system works without a central bank or single administrator.^[8]:1[9] The network is peer-to-peer and transactions take place between users directly through the use of cryptography, without an intermediary.^[8]:4 These transactions are verified by network nodes and recorded in a public distributed ledger called a blockchain. Bitcoin was invented by an unknown person or group of people under the name Satoshi Nakamoto^[10] and released as open-source software in 2009.^[11]

Bitcoins are created as a reward for a process known as mining. They can be exchanged for other currencies,^[12] products, and services. As of February 2015, over 100,000 merchants and vendors accepted bitcoin as payment.^[13] Research produced by the University of Cambridge estimates that in 2017, there are 2.9 to 5.8 million unique users using a cryptocurrency wallet, most of them using bitcoin.^[14]