Breast cancer is a familiar disease in the female; its effects are, however, not so much diverse in males. In females, the death rate is gradually increasing due to this disease because rarely its sign and symptoms appear at an initial phase that makes it hard to detect at an early stage. As breast cancer has developed into the rapidly growing disease among women, numerous detection methods, algorithms and new technologies and machinery are introduced in the market for its early detection. Computer aided diagnosis and detection system proved to be an efficient tool for early detection of breast tumor. Various techniques have been presented by researchers for the improved performance of CAD systems for diagnosis/detection of breast masses. The aim of this rese arch work is to present a concise review of different imaging modalities and techniques with their performance assessment in different stages of an automated or computer aided detection system (CAD) for breast tumor detection. The most commonly used imaging modalities are discussed like mammography, MRI, and ultrasound for breast cancer detection and diagnostic purposes. A detailed discussion of different imaging modalities, datasets, performance measures and various techniques used for the automated detection of a breast tumor with recent advances and evaluation of their performance in different steps of computer-aided diagnosis and detection systems is presented here.