To deal with security issues effectively, it is usually not sufficient to have knowledge of theories. Practical experience in dealing with these issues is essential. This book discusses the basic theories and also helps develop a practical outlook on the matter in a short and intriguing, manner. It provides readers with basic concepts and an awareness of industry standards and best practices. It answers questions such as "How do I know which cryptographic approach to be followed?", "How do I set a firewall?", "How do I secure specific network layers or application?", "How do I fight against application level attacks?", "How should I code securely?"