Compared to the traditional software several decades ago which were simple machine instructions or the combination of data structures and algorithms, current software are more complicated and harder to control and maintain. Normally, software systems are constructed through the assembly of components, whatever those which are developed according to new specifications or those which are stored in the libraries. In this circumstance, a team is needed to face different facets of the system. Some of them deal with the necessary functions to be implemented or reused in components, while others have to focus on how the work from different divisions can be coordinated and communicated correctly. Meanwhile, in this process some qualities of software must be guaranteed in order to approach the success.