Now a days most of the Linux desktops have their own Menu/launchers with search option like Ubuntu Unity has Dash, Gnome has Activities, KDE and Cinnamon has its own Menu, and so on. Launchers are used to search applications/files quickly as possible on finger tips. In past when Gnome didn't had Activities Menu then there was application Gnome-Do which still exist for current Linux versions but not widely used now and Gnome-Do is not been actively developed for a while. Native launchers can give you performance but if you want step forward and looking for an alternative for your Linux desktop then Synapse comes in handy.
![synapse](http://3.bp.blogspot.com/-xofAYs0SS5w/Ucwi8G1qsOI/AAAAAAAADt0/u0sx58BPhzA/s400/synapse.jpg)