sd card partitions

I now have a perfectly installed and up and running Volumio 2 on Pi3b with IQaudio Pi Digiamp+. Everything is running without fault.
The only query that I have is relating to the formatting/partitioning of the sd card.
I am using a card of 8gb as recommended. I noticed that during my initial setting up, I removed the sd card and ran it on my Win. 10 P.C.
through Wn32 Disk Imager. The card is shown on the P.C. as - drive E, drive F, drive G, with F and G saying that they need to be formated.
I assume that Volumio is installed on the first partition ( E ) Am I using all of the 8gb for Volumio or only a small part.
Am I right in thinking that Volumio2 expands the partition on first flashing of the card? Am I doing something wrong?

Thanks for guidance.

Hi, Volumio expands on its first boot to use all available space on SD Card.
Volumio needs 3 partitions:
1- Kernel and bootloader (this is the only one visible by windows)
2- System files
3- User data (where music, albumarts settings are stored)

You’re not doing anything wrong. And its’ normal that windows sees 3 partition but can read only 1

Hi Michelangelo.
Many thanks for your reply. I have read and understood.
I forgot to ask one thing. Is 8gb the best sd card capacity to use? I keep my music collection on a usb hdd and so will be putting nothing else on the sd card.

Jukebox Builder