There are many definitions of “Cybersecurity” and here you can see the one from CSEC2017 Joint Task Force (CSEC2017 JTF):
“Cybersecurity is a computing-based discipline involving technology, people, information, and processes to enable assured operations in the context of adversaries. It draws from the foundational fields of information security and information assurance; and began with more narrowly focused field of computer security.”
It consist of developing secure computer systems, their realization, analyzing and testing them.
Cybersecurity includes legislative aspects, politics, human factor and risk management.
Implementing effective cybersecurity measures is particularly challenging today because there are more devices than people, and attackers are becoming more innovative.” says the company CISCO.
