Process Required: Invoice does NOT have an approval process specified and will need one before it gets assigned to an approver. Note, this should not happen if Autonomous Approval Flows are correctly structured for your company.
Approval Process Specified: Invoice has an approval process specified, but it has not started yet.
In Progress: Invoice has been assigned to an approver and is currently pending approval. Note: Hovering over the icon allows you to check which step of the approval process the invoice is on (step 1, step 2, etc). If you see a small text bubble, the hover will also show the name and comment left by the initiator or approver.
Approved: Invoice is fully approved.
Rejected: Invoice was rejected by the approver(s), likely due to errors. You can check to see if any comments were left by the approver(s) by opening the side drawer using the keyboard shortcut "Shift + D" or by clicking the orange arrow icon.
Canceled: Approval process was started and then cancelled.
You can find these icons on the Approval column as seen below: