Escper is a Ruby library that makes printing of plain text and images to one or several serial thermal printers easy. USB, serial (RS232) and TCP/IP based printers are supported. Escper is useful for Ruby-based Point of Sale (POS) systems that want to print receipts, tickets or labels. Escper has been used as the printing 'engine' for my Point of Sale software Salor Hospitality. However, since I do no longer develop or maintain Salor Hospitality, I have no plans to develop or maintain this library any further. The version on Rubygems.org is upstream/1.2.2 and was working reliably with Ruby 1.9.3.