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Direct download link

A direct download link is a URL that delivers a file to the device for saving rather than displaying a hosted page, also known as a DD link.

Direct election: citizens vote directly for an officeholder rather than through electors or an electoral college. Contrasted with indirect election (India's presidency, US Electoral College); France adopted direct presidential suffrage in 1962; used in over half of countries with elected parliaments.

Direct electrical stimulation

Direct electrical stimulation is a neurosurgical mapping technique that passes brief electrical currents through exposed brain tissue during surgery, transiently disrupting function to identify eloquent areas before tumor resection.

Direct electrocortical stimulation

Direct electrocortical stimulation (ECS), also called direct electrical stimulation, is a neurosurgical technique that maps functional brain areas during surgery by stimulating the exposed cortex.

Direct electron detector

A direct electron detector is an imaging sensor for transmission electron microscopy in which electrons strike the semiconductor itself, improving efficiency and enabling high-frame-rate movie acquisition.

Direct energy conversion of field-reversed configuration exhaust

Direct energy conversion of field-reversed configuration exhaust turns the energy of an expanding FRC fusion plasma directly into electricity by electromagnetic induction, without a steam cycle.

Direct examination

Direct examination is the initial questioning of a witness at trial by the party that called the witness, conducted without leading questions and generally followed by cross-examination.

Direct fluorescent antibody technique

The direct fluorescent antibody (DFA) technique detects specific antigens directly in patient specimens using fluorescently labeled antibodies read under a microscope, giving results in about an hour.

Direct formic acid fuel cell

A direct formic acid fuel cell is a fuel cell that converts liquid formic acid directly into electricity, studied since the early 2000s for portable power.

Direct imaging (astronomy)

Direct imaging of exoplanets is an observational astronomy technique that records light from planets resolved from their host star, first achieving success with 2M1207b in 2004.

Direct impingement

Direct impingement is a gas operation for self-loading firearms in which propellant gas cycles the action directly, without a piston; it is best known from the AR-15.

Oct 21, 2026

Direct infections of joint

Direct infections of joint (ICD-11 FA10, Japanese 関節の直接感染) is a classification category for hematogenic or non-hematogenic joint infections, with child codes for bacterial, viral, and fungal joint infection, excluding reactive and postinfectious arthropathies.

Direct injection

Direct injection is an engine fuel-delivery method that sprays fuel directly into the combustion chamber, used in both diesel engines and, as gasoline direct injection, in spark-ignited cars.

Direct ink writing of liquid crystal elastomers

Direct ink writing of liquid crystal elastomers is an extrusion-based 3D printing method in which shear aligns the ink during extrusion, so the printed path programs molecular orientation and actuation.

Direct instruction

Direct instruction is an explicit, teacher-led teaching method using structured, sequenced lessons that move from teacher modeling to guided practice to independent practice with feedback, associated with Siegfried Engelmann.

Direct integral

A direct integral assembles a family of Hilbert spaces, von Neumann algebras, or operators indexed by a measure space, generalizing the direct sum of Hilbert spaces.

Direct kinematics of parallel manipulators

Direct kinematics of parallel manipulators, also known as forward kinematics, computes a platform's position and orientation from actuator leg lengths; the general six-degree-of-freedom problem has up to 40 solutions.

Direct laryngoscopy

Direct laryngoscopy is a procedure in which a rigid scope passed through the mouth gives direct visualization of the larynx, used for intubation, diagnosis, and surgery.

Direct laser deposition

Direct laser deposition, also called laser directed energy deposition, is an additive manufacturing method that melts metal powder or wire to build parts layer by layer.

Direct laser interference patterning

Direct laser interference patterning (DLIP) is a laser surface texturing method that splits one beam into coherent sub-beams, structuring surfaces at interference maxima without photoresist.

Direct liquefaction of biomass

Direct liquefaction of biomass is the family of thermochemical processes that turn biomass directly into biocrude, mainly by fast pyrolysis and hydrothermal liquefaction, then upgrade it to fuels.

Direct lithium extraction

Direct lithium extraction (DLE) is a family of chemical processes that extracts lithium from brines without solar evaporation, cutting brine-to-carbonate time from about a year to around a day.

Direct marketing

Direct marketing, also known as direct advertising, is promotional communication delivered to selected individuals or businesses through mail, email, telemarketing, and social media to generate a measurable response.

Direct measurement of the quantum wavefunction

Direct measurement of the quantum wavefunction is a technique demonstrated at the National Research Council of Canada in 2011 using a weak measurement followed by a strong one.

Direct memory access

Direct memory access (DMA) is a transfer strategy in which hardware moves data to or from memory without using the processor, freeing it for other tasks.

Direct metal deposition

Direct metal deposition (DMD) is a laser-based additive manufacturing process that melts powder or wire to build parts layer by layer and repair existing components.

Direct metal laser sintering

Direct metal laser sintering (DMLS) is an additive manufacturing process that uses a laser to fuse thin layers of metal powder into dense parts from CAD data.

Direct method (education)

The direct method is a foreign-language teaching approach, developed in the late nineteenth century against grammar-translation, that uses only the target language; Berlitz schools popularized it.

Direct methods (crystallography)

Direct methods are crystallographic techniques that estimate missing diffraction phases from intensities alone, developed by Karle and Hauptman, who won the 1985 Nobel Prize in Chemistry.