TATS is an acronym for tatting, a type of lace-making that uses a shuttle to create intricate patterns. Tatting is a form of handwork that has been around since the early 19th century and is still practiced today. It involves using a shuttle to pass thread through loops to create a decorative pattern. The shuttle is used to hold the thread and to move it through the loops. The end result is a delicate and intricate lace pattern.