Quora is a fast growing social Q&A site where users create and answer questions, and identify the best answers by upvotes and downvotes with crowd wisdom. Unfortunately, little is known about properties of experts and non-experts and how to detect experts in general topics or a specific topic. To fill the gaps, in this paper we (i) analyze behaviors of experts and non-experts in five popular topics; (ii) propose user activity features, quality of answer features, linguistic features and temporal features to identify distinguishing patterns between experts and non-experts; and (iii) develop statistical models based on the features to automatically detect experts. Our experimental results show that our classifiers effectively identify experts in general topics and a specific topic, achieving up to 97% accuracy and 0.987 AUC. In this paper, we are investigating and identifying potential experts who are providing the best solutions to the questioner needs. We have considered several techniques in identifying user as an expert or non-expert. We have targeted the most followed topics in Quora and finally came up with five topics: Mathematics, Politics, Technology, Sports and Business.We then crawled the user profiles who are following these topics. Each topic dataset has many special features. Our research indicates that experts are quite different from normal users and tend to produce high quality answers to as many questions as possible to gain their reputation. After evaluation, we got a limited number of experts who have potential expertise in specific fields, achieving up to 97% accuracy and 0.987 AUC.