Microevolution is a change in the gene pool of a single population across many generations. In contrast, Macroevolution is referring to major evolutionary changes, such as speciation and extinction, over the geological timescale. It is mainly used about the evolution of entire taxonomic groups (not just one population) over long periods of time.
Work Step by Step
Macroevolution is an entire taxonomic group's evolution; micro is following just one population.