Test is procedures for measuring ability, knowledge or performance. Testing can be defined as a method of assessment and improvement of the students. Language testing in any point is an extremely multifarious task that ought to be based on method as well as exercise. The results of assessments are used for one or more purposes. So they have an effect on those who are assessed and on those who use results. The knowledge of the fundamental doctrine of testing is important for the instructor, as instructors have to make test for the institution as well as for the candidates of the external examination. Many instructors to do have the right knowledge about testing so that the language test may have harmful effect on education any they fail to measure what they want to measure. This study aimed mainly of clarifications of notions of testing system, its impacts on education process and the different steps for a qualified test development. This article also presents the characteristics of good test as well as it presents a study which is based on the university students about the test technique that is commonly used in educational institution of Bangladesh. This article will be helpful for the instructors to develop their testing system and make their teaching an effective one for the students.