Sashiko (pronounced shash-ko) means 'stab stitch' and refers to the small running stitch that is worked to build up distinctive decorative patterns, of which there are hundreds.
The book begins by exploring the origins of the technique to strengthen clothes and to make them warmer. Getting Started describes everything you need to begin stitching, including selecting suitable fabrics and threads, marking out patterns on the fabric, as well as the stitching technique itself.