"Status" is the status of that specific membership transaction, "Current Status" is the overall status of the member. Status will always display the status for the specific transaction you are viewing. Current Status will always display the member's status based on their most recent membership transaction for this specific constituent.
For example, we are currently in the year 2024 and I am a member who purchased a 12-month membership on 2/1/2023. I then purchased a renewal on 2/1/2024. In the Details View on the Membership grid on the 2023 transaction record, my "Status" would be "Inactive”, and that membership has expired, but my "Current Status" would be "Active" as I have purchased a new membership that is currently "Active". In the Details View, the Status for each transaction can only be Inactive, Active, or Pending.
The Summary View of the Membership grid will only show the most recent membership transaction for the constituent, so only one record will be visible for each constituent in this view. In the example above, the transaction record shown on the Summary View grid that happened most recently in 2024 would have a Status of "Renewal" since it renewed the previous membership along with a Current Status of "Active." In the Summary View, the Status can be New, Renewal, Overdue, or Inactive.