How do I find out what filesystem my partitions are using?

There are a number of ways to do this from the command line (Ctrl+Alt+t):

The command df -T will print your filesystem types, as follows:

~$ df -T
Filesystem     Type      1K-blocks       Used Available Use% Mounted on
/dev/sda1      ext4      190230236  102672812  77894244  57% /
udev           devtmpfs    1021128         12   1021116   1% /dev
tmpfs          tmpfs        412884        816    412068   1% /run
none           tmpfs          5120          0      5120   0% /run/lock
none           tmpfs       1032208       2584   1029624   1% /run/shm
cgroup         tmpfs       1032208          0   1032208   0% /sys/fs/cgroup
/dev/sdb1      fuseblk  1953480700 1141530424 811950276  59% /home/user/storage

This article sums up several other methods of obtaining this information.

Here are a couple of other examples that I use occasionally:

~$ mount | grep "^/dev"
/dev/sda1 on / type ext4 (rw,errors=remount-ro)
/dev/sdb1 on /home/user/storage type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096)

~$ sudo file -sL /dev/sda1
/dev/sda1: Linux rev 1.0 ext4 filesystem data, UUID=b53ecdf7-5247-4d65-91a6-be9264c84dea (extents) (large files) (huge files)

You can also use the lsblk command like this:

$ sudo lsblk -f

NAME        FSTYPE LABEL      MOUNTPOINT
sda                           
├─sda1      ntfs   OS         
├─sda2      ntfs   Data       
├─sda3                        
├─sda5      ext4              /
└─sda6      swap              [SWAP]

A simple and good command

sudo blkid

It will list something like this:

/dev/sda1: LABEL="Windows" UUID="FA50DCB150DC763B" TYPE="ntfs" 
/dev/sda5: LABEL="40GBTWO" UUID="00A0CE7EA0CE7A24" TYPE="ntfs" 
/dev/sda6: UUID="7550252c-3da7-4cd9-8da3-71e9ba38e74a" TYPE="ext4" 
/dev/sda7: UUID="088fd084-a011-4896-aa93-c0caaad60620" TYPE="swap"

Where /dev/sda1 is the partition, LABEL is the given name to the partition, UUID is the Unique ID of the partiton which is quite useful to mount the hardisk using /etc/fstab, and TYPE is the file system.

I often use this command to get almost all the information about my hard drive and removal drive. Hope you too like it. :)

In the Dash type Disk and open the disk utility application, which is called either Disk Utility in Ubuntu 12.04 and Ubuntu 12.10, or Disks in Ubuntu 13.04 and later.

The screenshot shows the Disks window with the 500 GB Hard Disk selected to display information about that disk. In the center pane in the Volumes section you can see that the second partition on that hard disk has been selected to display information about that partition. In the Volumes section you can also see the description Contents: Ext4 which means that the partition is formatted as Ext4 which is the default Ubuntu filesystem format.

^{Disks in Ubuntu 18.04}

Try this in terminal:

sudo fdisk -l

Simply copy & paste the command into your terminal.

If I understand you correctly, this should show your drives.