When you chroot in Debian, bash shows the chroot environment in the prompt:
```bash
...
if [ -z "${debian_chroot:-}" ] && [ -r /etc/debian_chroot ]; then
debian_chroot=$(cat /etc/debian_chroot)
fi
PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
...
```
This is the effect:
```
(chroot_env) user@host:~#
```
It is useful when chrooting, since usually the hostname remains the same and thus you can't distinguish where you are.
