All articles starting with D
24,034 articles
Delta Dawn
Delta Dawn is a country and pop song written by Larry Collins and Alex Harvey. Helen Reddy's 1973 version reached number 1 on the Billboard Hot 100.
Delta del Orinoco Biosphere Reserve
Delta del Orinoco Biosphere Reserve (Reserva de Biosfera Delta del Orinoco), a UNESCO MAB site in Delta Amacuro, Venezuela, created 1991, covering 1,125,000 ha of Orinoco delta wetlands with Warao communities and endemic species.
Delta del Paraná Biosphere Reserve
Delta del Paraná Biosphere Reserve, a UNESCO MAB site designated in 2000 in Buenos Aires Province, Argentina, protecting 89,624 ha of freshwater tidal wetland in the Lower Paraná Delta near Buenos Aires.
Delta Delphini variable
A Delta Delphini variable is a chemically peculiar, evolved metallic-line A-type star that pulsates like a Delta Scuti star with a small light amplitude, named after Delta Delphini.
Delta Delta Delta
Delta Delta Delta (Tri Delta, ΔΔΔ) is a women's fraternity founded at Boston University on Thanksgiving Eve 1888 by Sarah Ida Shaw and Eleanor Dorcas Pond; NPC member, nearly 250,000 members, St. Jude philanthropy.
Delta du Fleuve Senegal Biosphere Reserve
Transboundary UNESCO biosphere reserve (2005) in the Senegal River delta spanning Senegal and Mauritania, covering 641,768 ha with over 350 bird species and 3 million migratory birds.
Delta du Saloum Biosphere Reserve
Delta du Saloum Biosphere Reserve (Réserve de Biosphère du Delta du Saloum), Senegal: UNESCO MAB site since 1980, Ramsar 1984, World Heritage 2011; 408,906 ha of mangroves, royal terns, and shell mounds.
Delta Electronics
Delta Electronics (台达电子) is a Taiwanese electronics company founded in 1971, making power supplies, liquid cooling, and automation, and is a leading AI data center supplier.
Delta encoding
Delta encoding is a data compression technique that stores differences between successive values or versions of data, underpinning revision control, software patching, and storage systems.
Delta Eridani
Delta Eridani, formally named Rana, is an orange subgiant star in the constellation Eridanus, about 29.5 light-years from the Sun and the constellation's fifth brightest star.
Delta ferrite
Delta ferrite is a magnetic, body-centered cubic iron phase retained, typically at a few weight percent, in austenitic stainless steel weld metal, where controlled amounts prevent hot cracking.
Delta Force
Delta Force (1st SFOD-D, also CAG or Army Compartmented Elements) is the U.S. Army's Tier 1 counterterrorism and hostage-rescue unit, founded by Colonel Charles Beckwith on the British SAS model in November 1977 at Fort Bragg and operating under JSOC.
Delta Force (2025 video game)
Delta Force (formerly Hawk Ops) is Team Jade and TiMi Studio Group's free-to-play tactical FPS reviving NovaLogic's 1998-2009 series, with 32v32 Warfare, Hazard Operations extraction, and a Black Hawk Down campaign; 246,418 Steam peak.
Delta Goodrem
Delta Goodrem, Australian singer-songwriter and actress born 1984 in Sydney; debut album Innocent Eyes (2003) went 23x platinum with five #1 singles; nine seasons coaching The Voice Australia; represented Australia at Eurovision 2026 with Eclipse, finishing fourth.
Delta Green
Delta Green is a contemporary cosmic-horror tabletop RPG, originally a 1992 Call of Cthulhu supplement by the Delta Green Partnership, standalone from Arc Dream Publishing since 2016 with Bonds, sanity, and Lethality mechanics.
Delta Heavy (group)
Delta Heavy are a London drum and bass duo of Ben Hall and Simon James, signed to RAM Records in 2010 and known for the 2012 single "Get By".
Delta II
The Delta II was an American expendable launch vehicle that flew 155 missions from 1989 to 2018, launching GPS satellites and NASA missions including the Mars rovers.
Delta Intelligence
Delta Intelligence (德塔智能) is a Beijing startup founded in 2026, spun out of BIGAI, that develops foundation models for humanoid robots and raised nearly RMB 500 million in 2026.
Delta IV
Delta IV, also known as Delta 4, was an American expendable rocket family developed by Boeing, whose Heavy variant was the United States' primary heavy-lift rocket.
Delta IV Heavy
Delta IV Heavy, also known as Delta 4 Heavy, was a heavy-lift rocket flown by United Launch Alliance from 2004 to 2024, largely for national security missions.
Delta Kappa Epsilon (ΔΚΕ)
Delta Kappa Epsilon (DKE, Deke) is a social fraternity founded at Yale College on June 22, 1844, with 15 founders; over 64 chapters, 85,000 members, five US presidents, and repeated hazing and misconduct sanctions.
Delta Lake
Delta Lake, born as Project Tahoe at Databricks in 2017, is an open-source ACID table format over Parquet files in data lakes, using a JSON transaction log (delta_log), MVCC, time travel, and connectors for Spark, Flink, and Trino.
Delta learning
Delta learning, also known as Δ-learning, is a machine learning strategy in computational chemistry that trains models to correct fast baseline quantum chemical calculations to near target-method accuracy.
Delta method
The delta method is a statistical technique that uses a Taylor expansion to approximate the variance or limit distribution of a function of a random quantity.
Delta modulation
Delta modulation is an analog-to-digital encoding method that represents a waveform with one bit per sample, sending whether the signal rose or fell; it underlies sigma-delta converters.
Delta neutral
Delta neutral describes a portfolio with zero net sensitivity to its underlying asset, built by hedging options with shares or futures and rebalanced as prices move.
Delta notation
Delta notation, also called the isotope delta, is the stable isotope geochemistry convention for reporting an isotope ratio as a relative difference from a reference material, in parts per mil.
Delta Oil Pipeline (United States)
The Delta Oil Pipeline is a Shell-owned crude oil pipeline carrying Heavy Louisiana Sweet crude from the eastern Gulf of Mexico to Louisiana terminals and refineries.
Delta operator
A delta operator is a shift-invariant linear operator on polynomials that lowers degree by exactly one, central to Rota's finite operator calculus of binomial-type polynomial sequences.
Delta Ophiuchi
Delta Ophiuchi, also known as Yed Prior, is a red giant star of the constellation Ophiuchus, visible to the naked eye at magnitude 2.75, about 160 light-years from the Sun.