Most people use the Dock on their Home screen for fast access to their favorite apps, but that isn’t the case for everyone; some jailbreakers, for example, run custom Home screen setups and may prefer to hide the Dock altogether.
If you fall into the latter group above, then you may take an interest in a new free jailbreak tweak dubbed DockRemover by iOS developer Blake Boxberger. As you've probably inferred from the name already, DockRemover hides the Dock from your iOS device’s Home screen, offering a cleaner overall aesthetic.