Another name for this pattern is Moss. This pattern is double-sided. Pattern is friable and stretchy. In order to make this pattern need to cast on an even number of stitches.
Row 1: *knit, purl*;
Row 2: *purl, knit*;
Further pattern is repeated from the first row.
Thus knit the knit stitches and purl the purl stitches.
A classical knit.
A classical purl.
How to Knit Charted Patterns with Needles
Symbols for Stitches and Knitting Techniques