Signal
Any piece of evidence, content, data, or behavior that search engines, AI systems, or people use to evaluate a digital entity.
A signal is anything that contributes to how a digital asset is understood, ranked, or trusted: content, links, structured data, mentions, user behavior, search impressions, AI citations, server logs, and marketplace activity all qualify.
Most organizations produce signals unintentionally, as a byproduct of running a website. Digital Signal Architecture treats signal production as a deliberate design choice instead.
Example
Publishing an article is a content signal. A third party linking to that article is a corroboration signal. A schema.org Article markup on the page is a structured data signal.
Nuance
Not all signals carry equal weight. A signal produced only on your own site is weaker evidence than the same claim corroborated independently elsewhere.