Reference Terms
from Wikipedia, the free encyclopedia
Web crawler
A web crawler (also known as a web spider or web robot) is a program or automated script which browses the World Wide Web in a methodical, automated manner. This process is called Web crawling or spidering. Many legitimate sites, in particular search engines, use spidering as a means of providing up-to-date data. Web crawlers are mainly used to create a copy of all the visited pages for later processing by a search engine, that will index the downloaded pages to provide fast searches. Crawlers can also be used for automating maintenance tasks on a Web site, such as checking links or validating HTML code. Also, crawlers can be used to gather specific types of information from Web pages, such as harvesting e-mail addresses (usually for spam).
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Computers & Math News
September 9, 2026
Sep. 7, 2026 A more realistic quantum model has revealed evidence that strange, nearly immobile quasiparticles called fractons could exist in solid materials. Their inability to move freely could make them promising building blocks for unusually robust quantum ...
Sep. 6, 2026 Scientists have devised a new way to switch magnetic computer memory while using far less energy than today's leading technologies. By mathematically optimizing the pulses used to flip digital bits, ...
Sep. 6, 2026 Princeton researchers have tested an AI system that can monitor and control fusion plasma in milliseconds, reacting far faster than a human operator. In one experiment, it predicted a damaging instability about 200 milliseconds before it appeared ...
Sep. 4, 2026 Harvard researchers have transformed ordinary knitting into a platform for creating fabrics that can snap between different shapes and perform useful functions. Using elastic yarns and industrial knitting techniques, the team engineered thick ...
Sep. 4, 2026 MIT researchers have created bacterial “transistors” that can be wired together into living circuits capable of performing calculations and directing chemical signals. One day, these biological computers could coat plant roots or leaves, ...
Sep. 3, 2026 Scientists at Carnegie Mellon University have discovered an unexpected form of the Hall effect, overturning the long-held assumption that this electrical response only appears when a magnetic field points perpendicular to a material. Beyond ...
Aug. 31, 2026 Scientists have uncovered hidden complexity inside two ultrathin superconductors that seemed much simpler than they really are. Niobium diselenide and tantalum disulfide appeared to have a single superconducting state, but highly sensitive ...
Aug. 31, 2026 Physicists have demonstrated a new way to entangle distant quantum bits without the constant measurements and active control normally required. The team created a “quantum bath,” a shared environment filled with correlated microwave photons that ...
Aug. 30, 2026 IBM and University of Chicago researchers have completed a quantum computation that leading classical methods could not practically reproduce. The system used 70 error-corrected logical qubits and finished the task in roughly 15 minutes while also ...
Aug. 27, 2026 Researchers used AI to search through more than 100 million possible settings for 3D-printing a high-performance NASA alloy. After only 40 experiments, the system identified six successful ...
Aug. 27, 2026 Scientists have found a surprising way to potentially switch on an unusual form of magnetism in ruthenium dioxide, a material that normally appears nonmagnetic. When the material was made into an ...
Aug. 26, 2026 NASA has successfully tested a system that allows satellites to navigate without GPS by using other spacecraft and debris as landmarks in orbit. In just three days, FALCON also improved the known orbits of more than 200 space objects completely ...
Latest Headlines
updated 12:56 pm ET
Aug. 30, 2026 Physicists have mathematically captured a bizarre “spacetime crystal” that can either dissolve or collapse into a microscopic black hole after only a tiny change in energy. Their breakthrough ...
Aug. 24, 2026 Researchers have created a tiny chip that produces a stable “rainbow” of light capable of generating multiple high-frequency signals at once, potentially boosting the speed and capacity of future ...
Aug. 24, 2026 More screen time during infancy and around the start of school was linked to poorer academic performance and weaker working memory years later. The findings suggest that early childhood may contain ...
Aug. 23, 2026 Researchers have used AI to uncover the DNA signature of a key genetic “switch” involved in turning genes on. After analyzing about 500,000 DNA sequences, the model identified the initiator in ...
Aug. 22, 2026 Freezing the liquid core of an optical fiber produced an extreme environment where light and sound interact more than 1,000 times more strongly than in ordinary fibers. Researchers used the effect to ...
Aug. 21, 2026 Scientists watched a light-triggered hidden state form inside a material in only 30 femtoseconds, revealing a step that had never been seen before. The material first entered a fleeting electronic ...
Aug. 18, 2026 Researchers have built microscopic, light-driven robots that can rapidly navigate through liquid, collect bacteria, and deposit them in chosen locations. These tiny “cleaners” could open new ...
Aug. 17, 2026 Caltech scientists have created ultra-low-loss optical pathways on silicon chips that approach the efficiency of fiber optics and dramatically outperform existing technology at visible wavelengths. ...
Aug. 17, 2026 Researchers combined synthetic DNA with a semiconductor to create an ultra-low-power memory device capable of storing and processing information in the same place. The bio-hybrid technology could ...
Aug. 17, 2026 An eight-year Finnish study found that children who spent more time on screens tended to show better cognitive processing as teenagers, challenging ...