Abstract
Cyber security plays an important role to secure the people who use internet via different electronic devices in their daily life. Some causes occurred all over world that people face problems when they connect their devices and system via internet. There are some highly sensitive data like biotechnology and military assets which are highly threatened by the hackers; cyber security plays a vital role in securing such data. Misusing the internet becomes a current issue in different sectors of life especially in social media, universities and government organizations. Internet is very useful for students in study institutes and employees who work in different organizations. Internet source gives the facility to people to fetch some information via internet. However, they must be protected when use the internet and secure for any unauthorized access. In this paper we have covered the different aspect of cyber security and Network security in the modern era. We have also tried to cover the threats in Intranet of organizations.