The quality of any software predominantly depends upon the software testing. Code coverage testing is one such technique that plays an important role to achieve the software for better quality and maintenance. The code coverage evaluates the testing effectiveness and provides data on different coverage items. Code coverage analysis measure what amount of source is covered by text execution. Using structural coverage, architectural coverage and requirement coverage the complete software testing can be measured. This review focus on techniques of structural coverage testing that is also known as code coverage testing. The code coverage can be done by some special analysis tools which are known as code coverage tools.