All articles starting with B

Backstroke

Backstroke: competitive swimming stroke swum on the back with alternating arms and flutter kick; only stroke started in the water; 15 m underwater limit; Olympic event since 1900.

Backstroke of the West, full title Star War: The Third Gathers – The Backstroke of the West, is a 2005 Chinese bootleg DVD of Star Wars: Episode III – Revenge of the Sith famous for machine-translated English subtitles and the "Do Not Want" meme.

Bäckström (Swedish TV series)

Bäckström is a Swedish crime drama (2020–2024) based on Leif GW Persson's Evert Bäckström novels, starring Kjell Bergqvist; three six-episode seasons on C More/TV4, distinct from the US series Backstrom.

Backsword

The backsword, also known as the Pallasch, is a straight, single-edged sword whose thickened spine adds stiffness for cutting, typically with a basket hilt; the term also names an English fencing tradition.

Backtesting

Backtesting is a validation method that evaluates a risk model, trading strategy, or forecasting rule by applying it to historical data; in banking, it compares daily value-at-risk forecasts with actual losses.

Backtracking

Backtracking, or backtracking search, is a class of algorithms for solving constraint satisfaction problems, formalized by Golomb and Baumert in 1965 and famously applied to the eight queens puzzle.

Backtracking (solar tracking)

Backtracking is a solar tracker control strategy that rotates panels away from the sun in early morning and late afternoon so one row does not shade the next.

Backtracking line search

Backtracking line search is an optimization procedure that repeatedly multiplies a trial step length by a constant factor until the Armijo sufficient-decrease condition holds, accepting the first adequate step.

Backup

A backup, also called a data backup, is a second copy of data kept so the original can be recovered after deletion, corruption, hardware failure, or ransomware.

Backup camera

A backup camera, also called a rearview camera, is a rear-facing camera showing the driver the area behind a vehicle, required on new US light vehicles since 2018.

Backus–Naur form

Backus-Naur form (BNF, Backus normal form), created by John Backus in 1959 and applied to ALGOL 60 by Peter Naur, is a production-rule notation for context-free grammars; extended as EBNF and ABNF (RFC 5234, STD 68) for Internet specifications.

Backward Bent Duct Buoy

The Backward Bent Duct Buoy (BBDB) is a floating wave energy converter with an L-shaped duct opening away from the waves, proposed by Yoshio Masuda in the 1980s.

Backward chaining

Backward chaining is a goal-driven inference method that starts from a hypothesis and works backward through rules to find supporting facts; it underlies Prolog and expert systems.

Backward compatibility

Backward compatibility lets newer consoles run older systems' games via hardware chips, emulation, recompilation, or streaming. Covers PS5 (99% of PS4 games), Xbox (~600 of 2,000+ Xbox 360 titles), Nintendo's shift to Switch Online, licensing barriers, and preservation trade-offs.

Backward design

Backward design, sometimes called understanding by design, is a curriculum planning method that sets learning goals and assessments before teaching activities, introduced by Grant Wiggins and Jay McTighe in 1998.

Backward differentiation formula

The backward differentiation formula (BDF) is a family of implicit linear multistep methods for stiff ordinary differential equations, first used in Curtiss and Hirschfelder's 1952 paper.

Backward diode

The backward diode, or back diode, is a tunnel diode variant that conducts better in reverse bias, used mainly as a zero-bias detector of small microwave signals.

Backward error analysis

Backward error analysis is a numerical analysis technique that judges a computed result by how much the input data must be perturbed for it to be exact.

Backward Euler method

The backward Euler method, also called implicit Euler, is a first-order implicit method for integrating ordinary differential equations, valued for its stability on stiff problems.

Backward induction

Backward induction is a game theory method for solving sequential games by determining optimal moves at each decision node, working from the end of the game back to the start.

Oct 10, 2026

Backward integration

Backward integration is a form of vertical integration in which a firm moves upstream to own the inputs it buys, aiming to cut costs and secure supply.

Backward stochastic differential equation

A backward stochastic differential equation (BSDE) is a stochastic equation solved backward from a terminal condition, used in finance, optimal control, and gene expression modeling.

Backward-wave oscillator

The backward-wave oscillator (BWO), also called the Carcinotron, is a vacuum electron tube that generates microwave oscillations by letting an electron beam interact with a backward-traveling wave.

Oct 10, 2026

Backwardation

Backwardation is the condition of a futures market in which the price for later delivery is below the spot price, the opposite of contango; it typically signals a tight physical market.

Backwashing

Backwashing is a water-treatment filter cleaning method that reverses flow upward through a granular bed or backward through a membrane, flushing out trapped particles to restore capacity.

Backyard Babies

Backyard Babies are a Swedish glam-punk and sleaze rock band formed in Nässjö in 1987 (originally Tyrant), with the unchanged lineup of Nicke Borg, Dregen, Johan Blomqvist, and Peder Carlsson; eight albums, two Grammis Awards, and number-one Swedish chart albums.

Backyard Baseball (1997 video game)

Backyard Baseball (1997) is Humongous Entertainment's point-and-click children's baseball game, first in the Backyard Sports series, with 30 fictional kids including Pablo Sanchez; remastered as Backyard Baseball '97 on Steam in 2024.

Backyard Baseball (2026 video game)

Backyard Baseball (2026) is an arcade baseball game by Mega Cat Studios and Playground Productions, released July 9, 2026 on Steam; a 3D Unity reimagining of the 1997 Humongous classic with 30 Backyard Kids, 11 stadiums, and no microtransactions.