UTF-8

From Wikipedia, the free encyclopedia

UTF-8 is a character encoding capable of encoding all possible characters, or code points, in Unicode.

The encoding is variable-length and uses 8-bit code units. It was designed for backward compatibility with ASCII, and to avoid the complications of endianness and byte order marks in the alternative UTF-16 and UTF-32 encodings. The name is derived from: Universal Coded Character Set + Transformation Format—8-bit.^[1]

Graph indicates that UTF-8 (light blue) exceeded other main encodings of text on the Web, that by 2010 it was nearing 50% prevalent, and up to 85% by August 2015.^[2] Encodings were detected by examining the text, not from the encoding tag in the header,^[3] and were sorted to the least inclusive set;^[4] thus, ASCII text tagged as UTF-8 or ISO-8859-1 is identified as ASCII.

UTF-8 is the dominant character encoding for the World Wide Web, accounting for 85.1% of all Web pages in September 2015 (with the most popular East Asian encoding, GB 2312, at 1.0%).^[2][3][5] The Internet Mail Consortium (IMC) recommends that all e-mail programs be able to display and create mail using UTF-8,^[6] and theW3C recommends UTF-8 as the default encoding in XML and HTML.

UTF-8 encodes each of the 1,112,064 valid code points in the Unicode code space (1,114,112 code points minus 2,048 surrogate code points) using one to four 8-bit bytes (a group of 8 bits is known as an octet in the Unicode Standard). Code points with lower numerical values (i.e., earlier code positions in the Unicode character set, which tend to occur more frequently) are encoded using fewer bytes. The first 128 characters of Unicode, which correspond one-to-one with ASCII, are encoded using a single octet with the same binary value as ASCII, making valid ASCII text valid UTF-8-encoded Unicode as well. And ASCII bytes do not occur when encoding non-ASCII code points into UTF-8, making UTF-8 safe to use within most programming and document languages that interpret certain ASCII characters in a special way, e.g. as end of string.

The official IANA code for the UTF-8 character encoding is UTF-8.^[7

https://en.wikipedia.org/wiki/UTF-8

Notepad

Notepad (software)

From Wikipedia, the free encyclopedia

Notepad

A component of Microsoft Windows
Notepad on Windows 8
Details
Type	Text editor
Included with	All Microsoft Windows versions
Related components
WordPad

Notepad is a simple text editor for Microsoft Windows and a basic text-editing program which enables computer users to create documents. It has been included in all versions of Microsoft Windows since Windows 1.0 in 1985.

Features[edit]

Notepad is a common text-only (plain text) editor. The resulting files—typically saved with the .txt extension—have no format tags or styles, making the program suitable for editing system files to use in a DOS environment and, occasionally, source code for later compilation or execution, usually through a command prompt. It is also useful for its negligible use of system resources; making for quick load time and processing time, especially on under-powered hardware. Notepad supports both left-to-right and right-to-left based languages. Unlike WordPad, Notepad does not treat newlines in Unix- or Mac-style text files correctly. Notepad offers only the most basic text manipulation functions, such as finding text. Only newer versions of Windows include an updated version of Notepad with a search and replace function. However, it has much less functionality in comparison to full-scale editors.

In all versions of Windows, Notepad uses a built-in window class named EDIT. Older versions included with Windows 95, Windows 98, Windows Me and Windows 3.1, imposed a 64 K limit on file size, which was an operating system limit of the EDIT class.

Up to Windows 95, Fixedsys was the only available display font for Notepad. Windows NT 4.0 and 98 introduced the ability to change this font. As of Windows 2000, the default font was changed to Lucida Console. The font setting, however, only affects how the text is shown to the user and how it is printed, not how the file is saved to disk. The default font was changed to Consolas on Windows 8.

Up to Windows Me, there were almost no keyboard shortcuts and no line-counting feature. Starting with Windows 2000, shortcuts for common tasks like new, open and save were added, as well as a status-bar with a line counter (available only when word-wrap is disabled).

In the Windows NT-based versions of Windows, Notepad can edit traditional 8-bit text files as well as Unicode text files (both UTF-8 and UTF-16, and in case of UTF-16, both little-endian and big-endian).

Notepad accepts text from the Windows clipboard. When clipboard data with multiple formats is pasted into Notepad, the program only accepts text in the CF_TEXT format.^[4] This is useful for stripping embedded font type and style codes from formatted text, such as when copying text from a web page and pasting into an email message or otherWYSIWYG text editor. Formatted text can be temporarily pasted into Notepad, and then immediately copied again in stripped format to paste into the other program.

Notepad can print files, but doesn't print correctly if Word Wrap is turned on. Headers, footers, and margins can be set and adjusted when preparing to print a file under Page Setup. The date, file name, and other information can be placed in the headers and footers with various codes consisting of an ampersand ('&') followed by a letter.

https://en.wikipedia.org/wiki/Notepad_(software)

History of mobile phones

A man talks on his mobile phone while standing near a conventional telephone box, which stands empty. Enabling technology for mobile phones was first developed in the 1940s but it was not until the mid 1980s that they became widely available. By 2011, it was estimated in the United Kingdom that more calls were made using mobile phones than wired devices.^[1]

This history focuses on communication devices which connect wirelessly to the public switched telephone network. Thetransmission of speech by radio has a long and varied history going back to Reginald Fessenden's invention and shore-to-ship demonstration of radio telephony. The first mobile telephones were barely portable compared to today's compact hand-held devices. Along with the process of developing more portable technology, drastic changes have taken place in the networking of wireless communication and the prevalence of its use.

Predecessors[edit]

Before the devices that are now referred to as mobile phones existed, there were some precursors. In 1908 a Professor Albert Jahnke and the Oakland Transcontinental Aerial Telephone and Power Company claimed to have developed a wireless telephone. They were accused of fraud and the charge was then dropped, but they do not seem to have proceeded with production.^[2] Beginning in 1918 the German railroad system tested wireless telephony on military trains between Berlin and Zossen.^[3] In 1924, public trials started with telephone connection on trains between Berlin and Hamburg. In 1925, the company Zugtelephonie A. G. was founded to supply train telephony equipment and in 1926 telephone service in trains of the Deutsche Reichsbahn and the German mail service on the route between Hamburg and Berlin was approved and offered to 1st class travelers.^[4]

Karl Arnold drawing of public use of mobile telephones

In 1907, the English caricaturist Lewis Baumer published a cartoon in Punch magazine entitled "Predictions for 1907" in which he showed a man and a woman in London's Hyde Park each separately engaged in gambling and dating on wireless telephony equipment. Then in 1926 the artist Karl Arnold created a visionary cartoon about the use of mobile phones in the street, in the picture "wireless telephony", published in the German satirical magazine Simplicissimus.^[5]

World Wide Web (WWW)

1980–1991: Invention and Implementation of the Web[edit]

The NeXTcube used by Tim Berners-Lee at CERN became the first Web server.

In 1980, Tim Berners-Lee, an independent contractor at the European Organization for Nuclear Research (CERN), Switzerland, builtENQUIRE, as a personal database of people and software models, but also as a way to play with hypertext; each new page of information in ENQUIRE had to be linked to an existing page.^[3]

Berners-Lee's contract in 1980 was from June to December, but In 1984 he returned to CERN in a permanent role, and considered its problems of information management: physicists from around the world needed to share data, yet they lacked common machines and any shared presentation software.

Shortly after Berners-Lee's return to CERN, TCP/IP protocols were installed on some key non-Unix machines at the institution, turning it into the largest Internet site in Europe within a few years. As a result, CERN's infrastructure was ready for Berners-Lee to create the Web.^[6]

Berners-Lee wrote a proposal in March 1989 for "a large hypertext database with typed links".^[7] Although the proposal attracted little interest, Berners-Lee was encouraged by his boss, Mike Sendall, to begin implementing his system on a newly acquired NeXT workstation.^[8] He considered several names, including Information Mesh,^[7] The Information Mine or Mine of Information, but settled on World Wide Web.^[9]

Robert Cailliau, Jean-François Abramatic and Tim Berners-Lee at the 10th anniversary of the WWW Consortium.

Berners-Lee found an enthusiastic supporter in Robert Cailliau. Berners-Lee and Cailliau pitched Berners-Lee's ideas to the European Conference on Hypertext Technology in September 1990, but found no vendors who could appreciate his vision of marrying hypertext with the Internet.^[10]

By Christmas 1990, Berners-Lee had built all the tools necessary for a working Web: the HyperText Transfer Protocol (HTTP) 0.9,^[11]the HyperText Markup Language (HTML), the first Web browser (named WorldWideWeb, which was also a Web editor), the first HTTP server software (later known as CERN httpd), the first web server and the first Web pages that described the project itself. The browser could access Usenet newsgroups and FTP files as well. However, it could run only on the NeXT; Nicola Pellow therefore created a simple text browser that could run on almost any computer called the Line Mode Browser.^[12] To encourage use within CERN, Bernd Pollermann put the CERN telephone directory on the web — previously users had to log onto the mainframe in order to look up phone numbers.^[12]

While inventing and working on setting up the Web, Berners-Lee spent most of his working hours in Building 31 at CERN (46.2325°N 6.0450°E), but also at his two homes, one in France, one in Switzerland.^[13] In January 1991 the first Web servers outside CERN itself were switched on.^[14]

The first web page may be lost, but Paul Jones of UNC-Chapel Hill in North Carolina revealed in May 2013 that he has a copy of a page sent to him in 1991 by Berners-Lee which is the oldest known web page. Jones stored the plain-text page, with hyperlinks, on a floppy disk and on his NeXT computer.^[15] CERN put the oldest known web page back online in 2014, complete with hyperlinks that helped users get started and helped them navigate what was then a very small web.^[16][17]

On August 6, 1991,^[18] Berners-Lee posted a short summary of the World Wide Web project on the alt.hypertext newsgroup, inviting collaborators.^[19] This date also marked the debut of the Web as a publicly available service on the Internet, although new users could only access it after August 23.

Paul Kunz from the Stanford Linear Accelerator Center visited CERN in September 1991, and was captivated by the Web. He brought the NeXT software back to SLAC, where librarian Louise Addis adapted it for the VM/CMS operating system on the IBM mainframe as a way to display SLAC’s catalog of online documents;^[12] this was the first web server outside of Europe and the first in North America.^[20] The www-talk mailing list was started in the same month.^[14]

An early CERN-related contribution to the Web was the parody band Les Horribles Cernettes, whose promotional image is believed to be among the Web's first five pictures.^[21]  

^{https://en.wikipedia.org/wiki/History_of_the_World_Wide_Web}

Tim Berners-Lee

From Wikipedia, the free encyclopedia

Sir Tim Berners-Lee
Berners-Lee in 2014.
Born	Timothy John Berners-Lee 8 June 1955 (age 60)[1] London, England
Institutions	World Wide Web Consortium University of Southampton Plessey MIT
Alma mater	University of Oxford (BA)
Notable awards	OM (2007) KBE (2004) FRS (2001)[2] FREng[when?] FRSA[when?] DFBCS (1995) See full list of honours
Spouse	Nancy Carlson (m. 1990)(divorced)[when?] Rosemary Leith (m. 2014)

Professor Sir Timothy John Berners-Lee, OM, KBE, FRS, FREng, FRSA, DFBCS (born 8 June 1955),^[1] also known as TimBL, is an English computer scientist, best known as the inventor of the World Wide Web. He made a proposal for an information management system in March 1989,^[3] and he implemented the first successful communication between a Hypertext Transfer Protocol (HTTP)client and server via the Internet sometime around mid-November of that same year.^{[4][5][6][7][8]}

Berners-Lee is the director of the World Wide Web Consortium (W3C), which oversees the Web's continued development. He is also the founder of the World Wide Web Foundation, and is a senior researcher and holder of the Founders Chair at the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL).^[9] He is a director of the Web Science Research Initiative (WSRI),^[10] and a member of the advisory board of the MIT Center for Collective Intelligence.^[11][12] In 2011 he was named as a member the Board of Trustees of the Ford Foundation.^[13]

In 2004, Berners-Lee was knighted by Queen Elizabeth II for his pioneering work.^[14][15] In April 2009, he was elected a foreign associate of the United States National Academy of Sciences.^[16][17] He was honoured as the "Inventor of the World Wide Web" during the 2012 Summer Olympics opening ceremony, in which he appeared in person, working with a vintage NeXT Computer at the London Olympic Stadium.^[18] He tweeted "This is for everyone",^[19] which instantly was spelled out in LCD lights attached to the chairs of the 80,000 people in the audience.^[18]

Memory card

Miniaturization is evident in memory card creation; over time, the physical card sizes grow smaller.

SanDisk HC Memory Card 32 GB with Adapter

A memory card or flash card is an electronic flash memory data storage device used for storing digital information. These are commonly used in portable electronic devices, such as digital cameras, mobile phones, laptop computers, tablets, MP3 players and video game consoles.

PC Cards (PCMCIA) were among first commercial memory card formats (type I cards) to come out in the 1990s, but are now mainly used in industrial applications and to connect I/O devices such as modems. In the 1990s, a number of memory card formats smaller than the PC Card arrived, including CompactFlash, SmartMedia, and Miniature Card. The desire for smaller cards for cell-phones, PDAs, and compact digital cameras drove a trend that left the previous generation of "compact" cards looking big. In digital cameras SmartMedia and CompactFlash had been very successful^{[neutrality is disputed]}. In 2001, SM alone captured 50% of the digital camera market and CF had captured the professional digital camera market. By 2005 however, SD/MMC had nearly taken over SmartMedia's spot, though not to the same level and with stiff competition coming from Memory Stick variants, as well as CompactFlash. In industrial and embedded fields, even the venerable PC card (PCMCIA) memory cards still manage to maintain a niche, while in mobile phones and PDAs, the memory card market was highly fragmented until 2010 when micro-SD came to dominate new high-end phones and tablet computers.

Since 2010, new products of Sony (previously only using Memory Stick) and Olympus (previously only using XD-Card) have been offered with an additional SD-Card slot.^[1]Effectively the format war has turned in SD-Card's favor.

https://en.wikipedia.org/wiki/Memory_card