The grapheme D (minuscule: d) is a letter in the Czech and Slovak alphabets. It is formed from Latin D with the addition of hácek and is placed right after regular D in the alphabet. It is used to denote , the voiced palatal plosive. It was also used in Polabian.

D (named dee ) is the fourth letter of the modern English alphabet and the ISO basic Latin alphabet.

The +D (or Plus D) was a floppy disk and printer interface for the Sinclair ZX Spectrum home computer, developed as a successor to Miles Gordon Technology's earlier product, the DISCiPLE. It was designed to be smaller, cheaper, simpler and thus more reliable.

D is the fourth letter of the Latin alphabet. It can also refer to the following:

• D, denoting the Federal Reserve Bank of Cleveland in the serial numbers of United States dollars
• D, Mitsubishi Electric's mobile phones in Japan
• D, the New York Stock Exchange ticker symbol for Dominion Resources
• D: All Things Digital, an annual technology conference sponsored by the Wall Street Journal, produced and hosted by columnist Walter Mossberg

D* (pronounced "D star") is any one of the following three related incremental search algorithms:

• The original D*, by Anthony Stentz, is an informed incremental search algorithm.
• Focused D* is an informed incremental heuristic search algorithm by Anthony Stentz that combines ideas of A* and the original D*. Focused D* resulted from a further development of the original D*.
• D* Lite is an incremental heuristic search algorithm by Sven Koenig and Maxim Likhachev that builds on LPA*, an incremental heuristic search algorithm that combines ideas of A* and Dynamic SWSF-FP.

D+ can refer to:

• D+ (band), indie rock band based in Anacortes, Washington
• Digital+, former name of Canal+ (Spanish satellite broadcasting company)
• D+, a grade (education)

D- means:

• Placed before a U.S. state, usually in parentheses, indicates the person it applies to is a Democratic Party politician of that state. "R-" is used for the Republican Party.
• An academic grade given by certain institutions. Slightly better than an F and slightly worse than a D. See Grade (education).
• A prefix signifying chirality of a molecule

D. can refer to, usually as an abbreviation:

• Don (honorific), a form of address in Spain, Portugal, Italy, and their former overseas empires, usually given to nobles or other individuals of high social rank.
• Date of death, as an abbreviation.
• District of Columbia Department of Transportation, whose logo is "d."
• Schubert Thematic Catalogue by O. E. Deutsch.

DamNation is a 2014 advocacy documentary film about the changing attitudes in the United States concerning the large system of dams in that country.

Damnation (from Latin ) is the concept of divine punishment and torment in an afterlife for actions committed on Earth. In Ancient Egyptian religious tradition, citizens would recite the 42 negative confessions of Maat as their heart was weighed against the feather of truth. If the citizen's heart was heavier than a feather they would face torment in a lake of fire. They all faced torment in a lake of fire. Zoroastrianism developed an eschatological concept of a Last Judgment called Frashokereti where the dead will be raised and the righteous wade though a river of milk while the wicked will be burned in a river of molten metal. Abrahamic religions such as Christianity have similar concepts of believers facing judgement on a last day to determine if they will spend eternity in Gehenna or heaven for their sin . A damned human "in damnation" is said to be either in Gehenna, or living in a state wherein they are divorced from Heaven and/or in a state of disgrace from God's favor. In traditional Abrahamic demonology, the Devil rules Gehenna, where he and his demons punish the damned.

Delta (uppercase Δ, lowercase δ or 𝛿; Délta; Modern Greek ) is the fourth letter of the Greek alphabet. In the system of Greek numerals it has a value of 4. It was derived from the Phoenician letter dalet . Letters that come from delta include Latin D and Cyrillic Д.

Detlef Soost (born July 2, 1970 in Berlin-Pankow, East Germany), also using the name D! (formerly Dee!), most often called Detlef D! Soost, is a German dancer and choreographer.

ETH Zurich (Swiss Federal Institute of Technology in Zurich, ) is an engineering, science, technology, mathematics and management university in the city of Zürich, Switzerland. Like its sister institution EPFL, it is an integral part of the Swiss Federal Institutes of Technology Domain (ETH Domain) that is directly subordinate to Switzerland's Federal Department of Economic Affairs, Education and Research.

An emoticon ( or ), etymologically a portmanteau of emotion and icon, is a metacommunicative pictorial representation of a facial expression that, in the absence of body language and prosody, serves to draw a receiver's attention to the tenor or temper of a sender's nominal non-verbal communication, changing and improving its interpretation. It expresses — usually by means of punctuation marks (though it can include numbers and letters) — a person's feelings or mood, though as emoticons have become more popular, some devices have provided stylized pictures that do not use punctuation.

In telecommunication, an End-of-Transmission character (EOT) is a transmission control character. Its intended use is to indicate the conclusion of a transmission that may have included one or more texts and any associated message headings.

Eth (, uppercase: Ð, lowercase: ð; also spelled edh or eð) is a letter used in Old English, Middle English, Icelandic, Faroese (in which it is called edd), and Elfdalian. It was also used in Scandinavia during the Middle Ages, but was subsequently replaced with dh and later d. It is transliterated to d (and d- is rarely used as a mnemonic). Its use has survived in Iceland and the Faroe Islands. The capital eth resembles a D with a line through the vertical stroke. The lower case resembles a reversed 6 with a line through the top. The lower-case letter has been adopted to represent a voiced dental fricative in the International Phonetic Alphabet.