In order to enhance the quality of software system metrics are considered as oneof the most important tools used in software engineering .They are concerned with measurement in software engineering (Fenton and Neil1999).Software metrics can be defined as means to supply meaningful and timely management information, together with the use of measurement based techniques to improve process and its products in software development. Acording to (Wakil and Fahmy, 2004) for estimation, quality control, productivity, assessment, and project control, software metrics are used to measure these throughout a software development life cycle. The software metric concept in which measurement-based techniques are applied to processes, products and services to supply useful engineering information. This information is further used to improve the processes, products and services. The information needed by engineers for technical decisions is provided by software metrics.