State the difference between virus and worm?

Parameter Virus Worm
How they infect a computer? It inserts malicious code into a specific file or program. Generate it’s copy and spread using email client.
Dependency Virus need a host program to work They do not require any host to function correctly.
Linked with files It is linked with .com, .xls, .exe, .doc, etc. It is linked with any file on a network.
Affecting speed It is slower than worm. It faster compared to a virus.