Such information can be found in section Dashboard, linked on the system's main menu:

In the left-top part of the Dashboard you can find a widget Today's Guest Summary:

Numbers in the left column refer to amount of persons, while right column shows amount of bookings.

1. Guests In-House Now - number of persons / bookings which stayed in property last night, but haven't been checked-out yet (or cancelled, or marked as no-shown) + number of persons / bookings which started their stay today and have been already checked-in

Bookings with statuses like Late/Confirmed/Arriving/New with a yesterday check-in date are also counted as "In House". If you haven't marked a booking as "NO-SHOWN" or "CANCELLED" it means that this booking is in hostel. Although we recommend you to keep an eye on statuses and set them up accordingly, depending on whether the guest has checked in or not.

2. Guests Arriving Today - number of persons / bookings which start their stay today, but haven't been checked-in yet

3. Guests Leaving - number of persons / bookings which are supposed to check-out today, but haven't done it yet.

4. Guests In-House Tonight - number of persons / bookings which are going to spend this night in the property. It is calculated as:
[4] = [1] + [2] - [3]
Where numbers above stands for: