\documentclass{scrartcl}
\usepackage[utf8x]{inputenc}
\usepackage{tabularx}
\usepackage[paper=letterpaper,top=1.0cm,bottom=1.0cm,left=1.2cm,right=1.2cm]{geometry}
\usepackage{graphicx}
\usepackage{pst-barcode}
\setlength{\parindent}{0pt}