Disk image storage allocation?

Could someone tell me what these partitions are? I am running Ubuntu 14.04.1 LTS and have 100% of storage allocated to one disk.

admin@localhost:~$ df -h

Filesystem Size Used Avail Use% Mounted on

/dev/xvda 24G 956M 23G 5% /

none 4.0K 0 4.0K 0% /sys/fs/cgroup

****devtmpfs 494M 4.0K 494M 1% /dev

none 99M 188K 99M 1% /run****

none 5.0M 0 5.0M 0% /run/lock

none 495M 0 495M 0% /run/shm

none 100M 0 100M 0% /run/user