All articles starting with X
1,563 articles
X-ray transient
An X-ray transient is an astronomical source whose X-ray emission appears, brightens, and fades over limited periods, often recurring, covering binary outbursts, stellar flares, and tidal disruption events.
X-ray tube
An X-ray tube, also called a conventional X-ray generator, is a vacuum device that produces X-rays by accelerating electrons into a metal anode, powering medical imaging and security screening.
X-rays
X-rays are high-energy electromagnetic radiation between ultraviolet light and gamma rays, discovered by Wilhelm Röntgen in 1895 and used in medical imaging, crystallography, and X-ray astronomy.
X-Treme X-Men
X-Treme X-Men is a Marvel Comics series written by Chris Claremont, running July 2001 to June 2004 for 46 issues, a Storm-led globetrotting X-Men team hunting Destiny's diaries, distinct from the 2012 Greg Pak series and the 2022-2023 Claremont/Larroca revival.
x-vector
An x-vector is a fixed-dimensional speaker embedding produced by a deep neural network, introduced by Snyder and colleagues at ICASSP 2018; it replaced i-vectors as the dominant speaker recognition approach.
X-Video Motion Compensation
X-Video Motion Compensation (XvMC) is an X Window System extension, designed for XFree86 in 2000, that offloads motion compensation and IDCT video decoding to graphics hardware.
X-VLA
X-VLA is a cross-embodiment vision-language-action robot policy introduced in October 2025 by Tsinghua AIR, Shanghai AI Laboratory, and Peking University, using per-source soft prompts to train one 0.9-billion-parameter model on seven robot platforms.
X-XSS-Protection
X-XSS-Protection is a deprecated, non-standard HTTP response header that controlled built-in browser filters for reflected cross-site scripting attacks, introduced in Internet Explorer 8 and replaced by Content-Security-Policy.
X: Past Is Present
X: Past Is Present is a 2015 Indian drama-mystery film by eleven directors including Sudhish Kamath and Nalan Kumarasamy, telling one story of filmmaker K (Rajat Kapoor) across eleven genre episodes, released 20 November 2015 by Drishyam Films.
X: The Man with the X-ray Eyes
X: The Man with the X-ray Eyes (1963), also released as The Man with the X-Ray Eyes, is a Roger Corman science fiction horror film starring Ray Milland as Dr. James Xavier, whose eye drops grant X-ray vision, and winner of the Silver Spaceship at the Trieste science fiction festival.
X:IN (엑신)
X:IN (엑신), a multinational five-member K-pop girl group debuted April 2023 under Escrow Entertainment; members E.Sha, Nizz, Hannah (Korea), Nova (Russia), Aria (India); releases include SYNCHRONICITY, THE REAL, Defend Myself, Hyper, Girls On Fire In Tokyo, and first studio album Chain Reaction.
X. Chris Le
X. Chris Le, also known as Xiao-Chun Le, is an environmental analytical chemist and Distinguished University Professor at the University of Alberta, elected to the Royal Society of Canada in 2010.
X. J. Kennedy
X. J. Kennedy (Joseph Charles Kennedy, 1929–2026) was an American formalist poet, children's author, and textbook editor; first book Nude Descending a Staircase won the 1961 Lamont Award, and he co-edited The Bedford Reader.
X. Peter Zhang
X. Peter Zhang, also known as Xiao-Xiang Zhang, is an organic chemist and full professor at Boston College known for developing metalloradical catalysis with Co(II) porphyrins.
X. William Yang
Xiangdong William Yang, known as X. William Yang, is a Chinese-born neuroscientist at UCLA known for engineered mouse models of Huntington's disease and research on DNA repair genes driving CAG-repeat expansion.
X.25
X.25, also known as the X.25 protocol suite, is a standard protocol suite approved by the CCITT in 1976, specifying how terminals connect to packet-switched public data networks.
X.500
X.500 is a series of ITU-T and ISO standards, first approved in 1988, defining a distributed directory service; its X.509 authentication framework underpins PKI certificates.
X.509
X.509 is an ITU-T standard, first published in 1988 as part of the X.500 Directory series, that defines public-key certificates and attribute certificates and underlies TLS on the internet.
X.AI Holdings Corp.
X.AI Holdings Corp. is the American holding company formed in March 2025 to combine Elon Musk's AI company xAI with his social media platform X, valuing them at $80 billion and $33 billion.
X.com (bank)
X.com was an American online banking company founded by Elon Musk in Palo Alto in 1999, which pivoted to PayPal payments and renamed itself PayPal in 2001.
X.Z. Shawn Xu
X.Z. Shawn Xu (许献忠) is a neuroscientist who established all six primary sensory modalities in the nematode C. elegans, identified sensory receptors including LITE-1, and studies how sensation regulates aging.
X's (album)
X's is the 2024 third studio album by American ambient pop band Cigarettes After Sex, released July 12, 2024 on Partisan/Spanish Prayers, written and produced by Greg Gonzalez about a four-year relationship; distinguishes from other X albums by band identity and ten dream pop tracks.
X'Trapolis 100
The X'Trapolis 100 is a single-deck electric multiple unit built by Alstom for suburban services, run by Metro Trains Melbourne since 2002 and also by Metro Valparaíso in Chile.
X/Gf
X/Gf is an inbred laboratory mouse strain developed by Anna Goldfeder, marked by extremely low spontaneous tumor incidence, resistance to several oncogenic viruses and carcinogens, and elevated natural killer cell activity.
X/Self
X/Self is a 1987 book-length poem by the Barbadian poet and historian Edward Kamau Brathwaite, completing his trilogy begun with Mother Poem (1977) and Sun Poem (1982).
X&Y
X&Y is Coldplay's third studio album, released 6 June 2005 on Parlophone. Produced by Ken Nelson, Danton Supple, and the band, it debuted at number one on Billboard, reached number one in 32 countries, and divided critics.
X+Y
X+Y (A Brilliant Young Mind) is a 2014 British drama by Morgan Matthews, inspired by his documentary Beautiful Young Minds, starring Asa Butterfield as autistic maths prodigy Nathan Ellis competing for the IMO.
X1 (band)
X1 (엑스원) was an 11-member South Korean project boy group formed on Mnet's Produce X 101, debuting August 27, 2019 with "Flash" from Quantum Leap and disbanding January 6, 2020 after the Mnet vote manipulation scandal.
X11 color names
X11 color names, from the X Window System's rgb.txt database of the mid-1980s, map names like "papaya whip" to fixed RGB triples and live on in web CSS.
X17 boson
The X17 boson is a hypothetical neutral particle of about 17 MeV, proposed to explain anomalous electron-positron pairs in beryllium-8 decays reported by the ATOMKI institute in Hungary in 2015.