# Sources (/docs/guides/sources)



Every lead and call in careCycle carries a **source**: the named origin it
came from, whether that is a lead vendor, a ping-post call vendor, your
website, or a mail campaign. Sources are how you answer the two questions
every agency owner asks about marketing spend: where did this member come
from, and which channels are actually converting.

<Cards>
  <Card title="Source Tracking" href="/docs/guides/sources/source-tracking">
    Create sources, assign them to campaigns, and compare performance so you
    know which channels earn their keep.
  </Card>

  <Card title="Ping-Post" href="/docs/guides/sources/ping-post">
    Already buying calls from vendors? Let them ping careCycle for agent
    availability before transferring, and track ping-to-call conversion.
  </Card>
</Cards>