Some of the most common types of cyber security attacks are viruses and worms. Computer viruses are categorized into five types: file infector, boot sector, master boot record, multipartite, and macro viruses. They alter the way a computer operates by using its own code to block a legitimate program’s execution code and by replicating themselves to infect network servers and other desktops. Depending on the type of virus that is infecting a computer, it may cause damage by deleting files and reformatting hard disks or simply make itself known by presenting audio and text messages to the user. However, the latter types often result in system crashes.
Computer worms are similar to viruses, but they are classified as a different type of cyber security attack. While viruses need a host file to replicate and spread, worms can replicate themselves across systems without using a host file and without human interaction. They are a stand-alone software. In most cases, they are found in various types of documents. However, once a worm has inserted itself into the document, it releases the document so that users can send the it freely. As the document travels, the worm infects each new computer in a similar fashion and continues to grow faster as more computers are infected.