Barcode
The standard barcode uses changes in lines and spaces to store numbers in a code that computers can read.  The lines are read by a scanner and changed into numbers. It is designed that it can be read forwards or backwards, so the user does not have to be careful how a product is put in front of the reader.  A laser line can be used to scan (read) the changes.  The laser scanners are also called barcode readers.  Since this laser line scans in one direction (left or right), this is called a 1D barcode.