Assessment plays a very important role in the teaching-learning process. It helps a learner to know his\her progress and the teacher to evaluate the progress of the students.Diagnostic Assessment:A diagnostic assessment is a pre-assessment where the teacher determines a student's strengths, weaknesses, and knowledge before giving an instruction.Diagnostic assessments are designed to help teachers identify what students know and can do in different domains to support their students' learning. This assessment is used only for specific purposes.For example, if a general achievement test indicates that students feel difficulty in comprehending the detailed explanation of the passages and sentence structures in a language, the teacher may use a diagnostic assessment for those students.Thus, it is concluded that she is conducting Diagnostic Assessment.Additional InformationPlacement Assessment: Placement assessment is conducted before the organization of teaching-learning activities to measure the entry behavior or previous knowledge of learners.Formative Assessment: The purpose of Formative Assessment is to know the progress of students and teachers during the instructional process. Any type of strategy and technique like asking questions, unit tests, etc. can be used for formative assessment by a teacher.Summative Assessment: Summative assessment is conducted to know the terminal behavior of the learner. The keyword in summative assessment is €œcertification€. A summative assessment is conducted after completion of the whole course.