Source

The word source has two meanings in analytics. In setup, a source is where data enters a project: a website running a tracking script, a backend that sends events, or an outside account whose data is imported. In reports, source often means where a visitor came from, as in the utm_source parameter or the phrase “traffic source”.

Keeping the two apart saves confusion. The first answers where your numbers come from; the second answers where your people come from.

In MIRA FIVE

A source is where data enters a project. A website source runs the script, a server source receives events from your backend, and Google Search Console and Google Ads connect as sources too. Website and server sources each have their own ingest keys: a website key for browsers, a secret key for servers. A new website source starts consentless: no cookies are set, nothing is stored on the device and no identifier is sent. Switched to Full, it accepts both kinds of data, and each page chooses the mode per visitor: the default setup, or full mode for visitors who consent.

Where people came from is called the channel. Acquisition sorts every visit into one of nine channels, from paid search to direct.

Example

A shop might run one website source for its storefront and one server source that reports paid orders from its checkout backend.