If you are new to cybersecurity, this book is for you. It is written in plain language. We try hard to not use too many jargons. When we have to use, we strive to explain them in plain language. The hands-on labs can be conducted on accompanied virtual machines installed with modern operating systems (Kali Linux, Metasploitable 2 and Windows 10/11) and have detailed instructions. After finishing the book, readers shall have a comprehensive understanding of cyber attack and security.