As long as the starting point is randomized, systematic sampling is a type of probability sampling.
StratifiedSampling Where the population embraces many distinct categories, the frame can be organized by these categories into separate "strata."
Stratifiedsampling can increase the cost and complicate the research design.
Quota Sampling In quota sampling, the population is first segmented into mutually exclusive subgroups, just as in stratifiedsampling.
Accidental Sampling Accidental sampling (or grab, convenience, or opportunity sampling) is a type of non-probability sampling which involves the sample being drawn from that part of the population which is close to hand.
Sampling is concerned with choosing a subset of individuals from a statistical population to estimate characteristics of a whole population.