Individuals and corporate user’s appetite to use email as one of the vital sources of communication. Email has become one of the part and parcel of our lives. Due to globalization, there is an extensive increase in the volume of emails received by a user. A particular user receives about 50-60 emails per day of different categories, for some users it may reach 100 emails. Out of these emails, most of them are not related to user interest. As the volume of emails receive continues to grow, the user has to spend a significant amount of time to process emails. It requires a system to manage these emails and to develop an automated classification system to classify emails into various categories as per the individuals and professional needs such as: academic, business, commercial. This paper presents a comprehensive review of several articles of email classification. The generic framework for email classification is devised and various steps in the framework are discussed in detail. The comparative analysis of various email classification techniques is discussed. The various challenges in the field of email classification are also presented.

E-mail classification, E-mail categorization, Text classification, Preprocessing techniques, Feature extraction and Machine learning techniques

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