samatha meditation is sometimes used as preparation for vipassana
samatha is not a form of meditation but a system of concentration that prepares the mind for deep vipassana meditation
samatha is about concentration, vipassana is about mindfulness
vipassana is aimed at insight or clearing the mind
vipassana is the ability to see things clearly
vipassana means to recognise the truth of something in a flash, suddenly understanding something
vipassana means having insight into the nature of life, actually feeling the truth of it as oppose to reading and understanding it
vipassana allows Buddhists to see what is causing their suffering, what they're attached to, what eightfold path steps and Bhrama Viharas they need to develop