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

They're "in memory" filesystems that don't use disk space. /dev is a special filesystem that holds device entries (eg /dev/xvda) and is populated at boot time. /run is a filesystem where programs can hold lock files or PID files.

_________________
Rgds
Stephen
(Linux user since kernel version 0.11)