Web development is the work involved in developing a web site for the Internet (World Wide Web) or an intranet (a private network). Web development can range from developing a simple single static page of plain text to complex web-based internet applications (web apps) electronic businesses, and social network services. A more comprehensive list of tasks to which web development commonly refers, may include web engineering, web design, web content development, client liaison, client-side/server-side scripting, web server and network security configuration, and e-commerce development. Among web professionals, "web development" usually refers to the main non-design aspects of building web sites: writing markup and coding. Most recently Web development has come to mean the creation of content management systems (CMS). These CMS can be made from scratch, proprietary or open source. In broad terms the CMS acts as middleware between the database and the user through the browser. A principle benefit of a CMS is that it allows non-technical people to make changes to their web site without having technical knowledge.

For larger organizations and businesses, web development teams can consist of hundreds of people (web developers) and follow standard methods like Agile methodologies while developing websites. Smaller organizations may only require a single permanent or contracting developer, or secondary assignment to related job positions such as a graphic designer or information systems technician. Web development may be a collaborative effort between departments rather than the domain of a designated department. There are three kinds of web developer specialization: front-end developer, back-end developer, and full-stack developer. Front-end developers deal with the layout and visuals of a website, while back-end developers deal with the functionality of a website. Back-end developers will program in the functions of a website that will collect data.

There are many open source tools for web development such as BerkeleyDB, GlassFish, LAMP (Linux, Apache, MySQL, PHP) stack and Perl/Plack. This has kept the cost of learning web development to a minimum. Another contributing factor to the growth of the industry has been the rise of easy-to-use WYSIWYG web-development software, such as Adobe Dreamweaver, BlueGriffon and Microsoft Visual Studio. Knowledge of HyperText Markup Language (HTML) or of programming languages is still required to use such software, but the basics can be learned and implemented quickly.An ever-growing set of tools and technologies have helped developers build more dynamic and interactive websites. Further, web developers now help to deliver applications as web services which were traditionally only available as applications on a desk-based computer. This has allowed for many opportunities to decentralize information and media distribution. Examples can be seen with the rise of cloud services such as Adobe Creative Cloud, Dropbox and Google Docs. These web services allow users to interact with applications from many locations, instead of being tied to a specific workstation for their application environment.Examples of dramatic transformation in communication and commerce led by web development include e-commerce. Online auction sites such as eBay have changed the way consumers find and purchase goods and services. Online retailers such as Amazon.com and Buy.com (among many others) have transformed the shopping and bargain-hunting experience for many consumers. Another example of transformative communication led by web development is the blog. Web applications such as WordPress and Movable Type have created blog-environments for individual websites. The increased usage of open-source content management systems and enterprise content management systems has extended web development's impact at online interaction and communication.Web development has also impacted personal networking and marketing. Websites are no longer simply tools for work or for commerce, but serve more broadly for communication and social networking. Web sites such as Facebook and Twitter provide users with a platform to communicate and organizations with a more personal and interactive way to engage the public.

Web development takes into account many security considerations, such as data entry error checking through forms, filtering output, and encryption. Malicious practices such as SQL injection can be executed by users with ill intent yet with only primitive knowledge of web development as a whole. Scripts can be used to exploit websites by granting unauthorized access to malicious users that try to collect information such as email addresses, passwords and protected content like credit card numbers

Photography is the art, application and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed in many fields of science, manufacturing (e.g., photolithography), and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication. Typically, a lens is used to focus the light reflected or emitted from objects into a real image on the light-sensitive surface inside a camera during a timed exposure. With an electronic image sensor, this produces an electrical charge at each pixel, which is electronically processed and stored in a digital image file for subsequent display or processing. The result with photographic emulsion is an invisible latent image, which is later chemically "developed" into a visible image, either negative or positive depending on the purpose of the photographic material and the method of processing. A negative image on film is traditionally used to photographically create a positive image on a paper base, known as a print, either by using an enlarger or by contact printing.

Several people may have coined the same new term from these roots independently. Hercules Florence, a French painter and inventor living in Campinas, Brazil, used the French form of the word, photographie, in private notes which a Brazilian historian believes were written in 1834.[5] This claim is widely reported but apparently has never been independently confirmed as beyond reasonable doubt.[citation needed] The German newspaper Vossische Zeitung of 25 February 1839 contained an article entitled Photographie, discussing several priority claims – especially Henry Fox Talbot's – regarding Daguerre's claim of invention. The article is the earliest known occurrence of the word in public print. It was signed "J.M.", believed to have been Berlin astronomer Johann von Maedler. Credit has traditionally been given to Sir John Herschel both for coining the word and for introducing it to the public. His uses of it in private correspondence prior to 25 February 1839 and at his Royal Society lecture on the subject in London on 14 March 1839 have long been amply documented and accepted as settled facts.

Wootton bridge collapse in 1861. The camera has a long and distinguished history as a means of recording scientific phenomena from the first use by Daguerre and Fox-Talbot, such as astronomical events (eclipses for example), small creatures and plants when the camera was attached to the eyepiece of microscopes (in photomicroscopy) and for macro photography of larger specimens. The camera also proved useful in recording crime scenes and the scenes of accidents, such as the Wootton bridge collapse in 1861. The methods used in analysing photographs for use in legal cases are collectively known as forensic photography. Crime scene photos are taken from three vantage point. The vantage points are overview, mid-range, and close-up. In 1845 Francis Ronalds, the Honorary Director of the Kew Observatory, invented the first successful camera to make continuous recordings of meteorological and geomagnetic parameters. Different machines produced 12- or 24- hour photographic traces of the minute-by-minute variations of atmospheric pressure, temperature, humidity, atmospheric electricity, and the three components of geomagnetic forces. The cameras were supplied to numerous observatories around the world and some remained in use until well into the 20th century. Charles Brooke a little later developed similar instruments for the Greenwich Observatory.

Users typically access social media services via web-based technologies on desktops and laptops, or download services that offer social media functionality to their mobile devices (e.g., smartphones and tablets). When engaging with these services, users can create highly interactive platforms through which individuals, communities, and organizations can share, co-create, discuss, and modify user-generated content or pre-made content posted online. They "introduce substantial and pervasive changes to communication between organizations, communities, and individuals." Social media changes the way individuals and large organizations communicate. These changes are the focus of the emerging fields of technoself studies. Social media differ from paper-based media (e.g., magazines and newspapers) to traditional electronic media such as TV broadcasting in many ways, including quality,reach, frequency, interactivity, usability, immediacy, and performance. Social media outlets operate in a dialogic transmission system (many sources to many receivers).This is in contrast to traditional media which operates under a monologic transmission model (one source to many receivers), such as a newspaper which is delivered to many subscribers, or a radio station which broadcasts the same programs to an entire city. Some of the most popular social media websites are Baidu Tieba, Facebook (and its associated Facebook Messenger), Google+, Myspace, Instagram, LinkedIn, Pinterest, Snapchat, Tumblr, Twitter, Viber, VK, WeChat, Weibo, WhatsApp, and Wikia. These social media websites have more than 100,000,000 registered users.

Social media have a history dating back to the 1970s.ARPANET, which first came online in 1967, had by the late 1970s developed a rich cultural exchange of non-government/business ideas and communication, as clearly evidenced by ARPANET#Rules and etiquette's "A 1982 handbook on computing at MIT's AI Lab stated regarding network etiquette," and fully met the current definition of the term "social media" found in this article. Usenet, which arrived in 1979, was beat by a precursor of the electronic bulletin board system (BBS) known as Community Memory in 1973. True electronic bulletin board systems arrived with the Computer Bulletin Board System in Chicago, which first came online on 16 February 1978. Before long, most major cities had more than one BBS running on TRS-80, Apple II, Atari, IBM PC, Commodore 64, Sinclair, and similar personal computers. The IBM PC was introduced in 1981, and subsequent models of both Mac computers and PCs were used throughout the 1980s.

Some social media sites have potential for content posted there to spread virally over social networks. The term is an analogy to the concept of viral infections, which can spread rapidly from person to person. In a social media context, content or websites that are "viral" (or which "go viral") are those with a greater likelihood that users will reshare content posted (by another user) to their social network, leading to further sharing. In some cases, posts containing popular content or fast-breaking news have been rapidly shared and reshared by a huge number of users. Many social media sites provide a specific functionality to help users reshare content, such as Twitter's retweet button, Pinterest's pin function, Facebook's share option or Tumblr's reblog function. Businesses have a particular interest in viral marketing tactics because a viral campaign can achieve widespread advertising coverage (particularly if the viral reposting itself makes the news) for a fraction of the cost of a traditional marketing campaign, which typically uses printed materials, like newspapers, magazines, mailings, and billboards, and television and radio commercials. Nonprofit organizations and activists may have similar interests in posting content on social media sites with the aim of it going viral. A popular component and feature of Twitter is retweeting. Twitter allows other people to keep up with important events, stay connected with their peers, and can contribute in various ways throughout social media.[26] When certain posts become popular, they start to get tweeted over and over again, becoming viral. Ellen DeGeneres is a prime example of this. She was a host during the 86th Academy Awards, when she took the opportunity to take a selfie with a dozen others, including Jennifer Lawrence, Brad Pitt and Julia Roberts.[29] This picture went viral within 40 minutes and was retweeted 1.8 million times within the first hour. This was an record for Twitter and the use of selfies, which other celebrities have tried to copy. In May 2017, Carter Wilkerson's tweet at Wendy's asking what it would take to get free chicken nuggets for a year surpassed Ellen DeGeneres' famous tweet with over 3 million retweets.