Made wording a bit more generic.
@@ -155,7 +155,7 @@ string is equivalent to setting the `--tlsverify` flag. The following are equiva
### Daemon storage-driver option
-The Docker daemon has support for four different image layer storage drivers: `aufs`,
+The Docker daemon has support for several different image layer storage drivers: `aufs`,
`devicemapper`, `btrfs` and `overlayfs`.
The `aufs` driver is the oldest, but is based on a Linux kernel patch-set that
