In a sampling technique, every 10th unit of population is chosen. What is this type of sampling technique called?

Systematic random sampling is a sampling technique. It is done by picking up every 5th or 10th unit at regular intervals. By this method, each in the sampling frame would have the same chance of being selected, but the number of possible samples is reduced. Other sampling methods are simple random sampling, stratified random sampling. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 913