The difference between the two Barcode symbology types, Code 128 and Data Matrix

A barcode’s symbology is the encoding of information into the barcode image. While numerous barcode symbologies exist, Code 128 and Data Matrix are among the most commonly used. 

1. Code 128 is a one-dimensional (1D), linear barcode symbology. It is used for alphanumeric or numeric-only barcodes. 
2. Data matrix is a two-dimensional (2D) code consisting of black and white "dots" or dots arranged in either a square or rectangular pattern, also known as a matrix. The information to be encoded includes up to 2,335 characters of alphanumeric data.