Student assessment falls into two general categories: formative (assessment for learning) and summative (assessment of learning).
Formative assessment happens while learning is still underway. Teachers use these assessments to diagnose student needs, plan next steps of instruction, provide students with feedback they can use to improve the quality of their work, and help students see and feel in control of their journey to success.
Summative assessments are those assessments that happen after learning is supposed to have occurred to determine if it did. They are used to make statements of student learning status at a point in time to those outside the classroom. State assessments and college entrance assessments are examples of summative assessments.