&quot;via&quot; comes from latin, it means &quot; a place to travel trough&quot;.<p>For example in Spain &quot;autovia&quot; means via for autos or &quot;tranvia&quot; means a vehicle that goes over rails. &quot;Via pecuaria&quot; means a road for animal transport.<p>You can do lots of useful things with just two layers. We prototype professional electronics in house with just two layers and modules(over a big area), then shrink the design, use more layers and get it done using a professional service.