Common envelope binaries with a third component

In this thesis, common-envelope evolution and post common-envelope evolution of binary stars were studied from a review of available literature. A post common envelope binary system NSVS14256825 was observed at the TÜBİTAK National Observatory using T100 telescope. The light variation of the system was analyzed with the radial velocity curve of the system given in the literature. The times of minimum light obtained in this study were combined with the times of minimum light presented in the literature to study the O-C variation of the system. The results presented with a discussion of earlier studies. The preliminary results obtained so far indicate a probability for the binary system to have two planetary components.