Once only offered as an aluminium box full of fluorescent tubes unless they were neon, most of today's signs are lit using l.e.d. technology which have many benefits, not least stronger lighting and low maintenance.
These can be anything from back-lit individual built up lettering and logos to full size fret cut trays back lit in a choice of colours.
A great way to increase viability and attract potential custom. Whichever you choose they will be sure to give you a high profile once dusk falls.