malicious software such as viruses, spyware and malware, assignment help

Chapter 11 of the text discusses malicious software such as viruses, spyware and malware. Most people using desktop computers in the past two decades have come across these items at some point or another. What are viruses? What is spyware? What tools and practices can be employed to help prevent such items from getting on your computer?I am attaching my course E book for your reference so please be specific about the topic and please be specific about it in Apa format three references, cover all the topics in the question in detail in 500 words