Credit card is one of the most extensive methods of instalment for both online and offline mode of payment for electronic transactions in recent times. credit cards invention has provided significant ease in electronic transactions. However, it has also provided new fraud opportunities for criminals, which results in increased fraud rates. Substantial amount of money has been lost by many institutions and individuals due to fraudulent credit card transactions. Adapting improved and dynamic fraud recognition frameworks thus became essential for all credit card distributing banks to mitigate their losses. In fact, the problem of fraudulent credit card transactions implicates a number of relevant real-time challenges, namely: Concept drift, Class imbalance, and Verification latency. However, the vast majority of current systems are based on artificial intelligence (AI), Fuzzy logic, Machine Learning, Data mining, Genetic Algorithms, and so on, rely on assumptions that hardly address all the relevant challenges of fraud-detection system (FDS). This paper aims to understand & implement Deep Learning algorithms in order to obtain a high fraud coverage with very low false positive rate. Also, it aims to implement an auto-encoder as an unsupervised (semi-supervised) method of learning common patterns. Keywords: Credit card fraud, Fraud-detection system (FDS), Electronic transactions, Concept drift, Class imbalance, Verification latency, Machine Learning, Deep Learning