Ripstop is a woven fabric which uses a reinforcing technique that makes them resistant to tearing and ripping. During weaving, a thicker (or a number of fine) reinforcement threads are interwoven at regular intervals in a crosshatch pattern. The intervals are typically 5 to 8mm. Lightweight ripstop fabrics have a 3-dimensional structure due to the thicker threads being interwoven in thinner cloth. The benefit of a ripstop fabric is that it has a high strength to weight ratio with tears being contained by the heavier reinforcing yarns. 

Take a look at the shirts available in this fabric here