Sequencer

A sequencer is a device or software that arranges events in a specific order over time. In diverse contexts, sequencers automate the timing and order of actions, from musical notes to experimental steps to digital operations.

In music technology, sequencers store patterns that trigger notes or control parameters at defined times. They can be hardware devices or software in a digital audio workstation. Common types include step sequencers, which advance through fixed patterns; polyphonic sequencers for multiple voices; and MIDI sequencers that output MIDI events. Modern sequencers often offer piano-roll editors, automation lanes, and synchronization with other devices.

In molecular biology, sequencing determines the order of nucleotides in a biological polymer. Sequencers are instruments that generate sequence data from DNA, RNA, or proteins. DNA sequencing methods include Sanger sequencing and high-throughput next-generation sequencing (NGS) platforms such as Illumina and Ion Torrent, as well as long-read platforms like PacBio SMRT and Oxford Nanopore. Output consists of sequence reads that are assembled into genomes or used for analysis.

In computing and automation, a sequencer controls a sequence of operations—timed events, data flows, or motor movements. It can be integrated into test equipment, laboratory automation, or industrial control systems. Implementations range from simple software routines to hardware modules or programmable logic controllers.