After downloading the latest stable version of Crate Data from https://crate.io/downloads/ the package needs to be unpacked:
sh$ tar zxf crate-*.tar.gz
Now Cate can be started in the foreground like this:
sh$ ./bin/crate -f
In order to start in the background omit the -f option. If started in the foreground you can use Control-C to stop the process again.
Note
Crate Data needs a working Java >= 1.7 installation in order to run.
See also