Filter

For Wikipedia's edit/abuse filter, seeSpecial:AbuseFilterandWikipedia:Edit filter.

Filtrationis a physical process that separates solid matter and fluid from a mixture.

Filter,filtering,filtersorfiltrationmay also refer to:

Science and technology

Computing

• Filter (higher-order function),in functional programming
• Filter (software),a computer program to process a data stream
• Filter (video),a software component that performs some operation on a multimedia stream
• Email filtering,the processing of email to organize it according to specified criteria
• Content-control softwarealso known as an Internet filter
• Wordfilter,a script typically used on Internet forums or chat rooms
• Berkeley Packet Filter,filter expression used in the qualification of network data
• DSL filter,a low-pass filter installed between analog devices and a telephone line
• Helicon Filter,a raster graphics editor
• Filter (large eddy simulation),a mathematical operation intended to remove a range of small scales from the solution to the Navier-Stokes equations
• Kalman filter,an approximating algorithm in optimal control applications and problems

• Filter (social media),an appearance-altering digital image effect for social media

Device

• Filter (chemistry),a device which separates solids from fluids (liquids or gases) by adding a medium through which only the fluid can pass
  • Filter (aquarium),critical components of both freshwater and marine aquaria
  • Filter paper,a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine solids from liquids or air
  • Air filter,a device composed of fibrous materials which removes solid particulates such as dust, pollen, mold, and bacteria from the air
  • Oil filter,a filter to remove contaminants from engine oil, transmission oil, lubricating oil, or hydraulic oil
  • Pneumatic filter,a device which removes contaminants from a compressed air stream
  • Water filter,removes impurities from water by means of a fine physical barrier, a chemical process or a biological process
  • Cigarette filter,a part of a cigarette intended to filter the smoke inhaled by a smoker
  • Coffee filter,a utensil used to separate coffee grounds from liquid coffee
  • Fuel filter,found in most internal combustion engines
  • Filtration (wine)
• Sieveor macroscopic filter, a device for separating wanted elements from unwanted material

Mathematics

• Filter (mathematics),a special subset of a partially ordered set.
• Filter (set theory),a special family of subsets that forms an (order theoretic) filter with respect to set inclusion
• Filters in topology,the use of collections of subsets to describe convergence.
• Filtering problem (stochastic processes),a mathematical model for a number of filtering problems in signal processing and the like.
• Filtration (mathematics),an indexed set of subobjects of a given algebraic structure S.

Optics

• Optical filter,selectively transmits light of different wavelengths
  • Interference filter,reflects one or more spectral bands or lines and transmits others, while maintaining a nearly zero coefficient of absorption for all wavelengths of interest
  • Dichroic filter,a very accurate color filter used to selectively pass light of a small range of colors while reflecting other colors
  • Hydrogen-alpha filter,an optical filter that transmits a narrow bandwidth of light centred on the H-alpha wavelength
  • Photographic filter,a camera accessory consisting of an optical filter that can be inserted in the optical path
  • Infrared cut-off filter,designed to reflect or block mid-infrared wavelengths while passing visible light
  • Chelsea filter,a dichromatic optical filter used for identifying coloured stones
  • Astronomical filter,a telescope accessory used to enhance the details of celestial objects

Signal processing

• Filter (signal processing)
  • Electronic filter,an electronic circuit which processes signals, for example to remove unwanted frequency components
  • Digital filter,a system that performs mathematical operations to reduce or enhance certain aspects of a signal
  • Analogue filter,a basic building block of signal processing much used in electronics
  • Filters used indigital image processing

Arts and entertainment

• Filter(TV series),a show on the G4 channel
• Filter(magazine),an indie music magazine
• Filter Theatre,a British theatre company
• The Filter,a digital content services company based in England
• Filter (band),an American rock band
• "Filter", a song from the albumBendby 8stops7
• "Filter", a song from the albumMap of the Soul: 7by BTS
• "Filter", a song from the albumRubyby Jennie

Other uses

• Biofilter,a pollution control technique using a bioreactor containing living material to capture and biologically degrade pollutants
• Filtering (housing),the process of housing units becoming more affordable with age
• Category-based filtering of perception, according to (objectivist interpretations of) Kant
  • Affective filter,an impediment to learning or acquisition caused by negative emotional ( "affective" ) responses to one's environment
• Lane splitting,a practice that cyclists use to pass slow or stopped congested traffic
• The ability of a person to self-censorthemselves (their thoughts) whilst speaking

See also

• Filter coffee,a method for preparing coffee
• Filter feeder,an animal that strains food particles from water
• Filtration camp (disambiguation)
• Lifter (signal processing)
• Philtre (disambiguation)
• Separation process
• Ultrafilter