there are two types of test design techniques
they are
1.Boundary value analysis.
2.Equilance class partition.

Boundary value analsys: if there is a range kind of input 
the technique used by the test engineer to dovelop the test 
cases for that range is called as boundary value analsys.

equilance class partition: here the test engineer writes 
the valied and invalied test cases i.e. positive test cases 
and negative test cases.