Unknown

Unknown or The Unknown may refer to:

Mathematics

Film

Music

Other uses

Blu-ray

Blu-ray or Blu-ray Disc (BD, BRD) is a digital optical disc data storage format. It was designed to supersede the DVD format, in that it is capable of storing high-definition video resolution (1080p). The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Conventional (pre-BD-XL) Blu-ray Discs contain 25 GB per layer, with dual layer discs (50 GB) being the industry standard for feature-length video discs. Triple-layer discs (100 GB) and quadruple-layers (128 GB) are available for BD-XL re-writer drives. The name "Blu-ray" refers to the blue laser (specifically, a violet laser) used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs. The main application of Blu-ray is as a medium for video material such as feature films and physical distribution of video games for the PlayStation 3, PlayStation 4, and Xbox One. Besides the hardware specifications, Blu-ray is associated with a set of multimedia formats.

8th millennium

The eighth millennium of the Gregorian calendar will begin on January 1, 7001, and end on December 31, 8000. It will be the eighth millennium in the Anno Domini or Common Era.

Astronomical events

All these dates are in a uniform time scale such as Terrestrial Time. When converted to our ordinary solar time or Universal Time, which is decidedly non-uniform, via ΔT, the dates would be about one day earlier.

UTF-8

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.

UTF-8 is the dominant character encoding for the World Wide Web, accounting for 86.2% of all Web pages in January 2016 (with the most popular East Asian encoding, GB 2312, at 0.9% and Shift JIS at 1.1%). The Internet Mail Consortium (IMC) recommends that all e-mail programs be able to display and create mail using UTF-8, and the W3C 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.