markersystems

Marker systems are methods that assign signals, labels, or cues to objects, locations, or phenomena to enable identification, tracking, and measurement within a larger process or environment. They can be physical devices, digital encodings, or biological markers, and are chosen to match the needs of accuracy, throughput, and durability.

Physical marker systems include barcodes, QR codes, RFID tags, and color-coded labels. They convey identity and sometimes status or location, and are read by scanners, cameras, or readers. The choice among them depends on data capacity, environmental resistance, speed, and cost. Barcodes are cheap and simple; RFID offers longer range and reusability; QR codes store more data; color codes can be interpreted by machine vision under controlled lighting.

Biological marker systems (genetic markers) use specific DNA sequences or phenotypic traits to identify individuals, populations, or traits. DNA markers include SNPs, microsatellites (SSRs), RFLP, AFLP, and copy-number variation markers. They enable linkage mapping, quantitative trait locus analysis, parentage and identity testing, and biodiversity studies. Marker systems underpin modern breeding programs and forensic genetics, and they support ecological and evolutionary research by providing standardized, verifiable signals.

In computing and documentation, marker concepts appear as annotation markers, bookmarks, or metadata tags used to flag regions of text, code, or data collections, supporting navigation and data processing. Selecting a marker system involves evaluating reliability, scalability, readout speed, environmental constraints, cost, and integration with existing workflows.