Basic Computer Viruses

-took over free space on the floppy disk and hid from detection ”disguised itself by displaying the uninfected boot sector on the disk.”

1987-Lehigh virus

- the first memory resident file infector that attacked executable files and took control when a file was opened

The Jerusalem Virus

-had bugs that re-infected programs that were already infected

1988: Robert Morris made a worm that invaded ARPANET computers

• 1988: Robert Morris made a worm that invaded ARPANET computers
• disabled 6,000 computers on the network by overflowing their memory banks with copies of itself
• 1991: Norton Anti-Virus software
• 1999: "Melissa" virus