The sending log is a live view of everything your workspace is sending — queued, in flight, and recent history — in one place.
Go to Settings → Sending log. Each row's subject and From are derived from the campaign, sequence, or mailbox attached to the message, so you can trace exactly what went out and from where.
It's the first place to look when you want to confirm a send actually happened, check whether something is still queued, or investigate a delivery question. Paired with the Deliverability stats, it gives you a complete picture of your sending activity and health.