hi
hi first let me wish you Happy Holi ( the festival of colors)

And for the Difference between Worm and A virus. the basic difference to me is that a virus needs a host program a worm does not it propagets thrioug the network without any human intervintion
for more Check this out and This

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I found this one interseting too
A virus is a file that cannot spread to other computers unless a infected file is copied and sent manualy to another computer were as a worm just does the opposite:

A worm is a wonderous creation that once in your machine usually copies itself and spreads using, irc, outlook or n e other applicable mailing unit, or as blaster just recently showed us using exploitations in ports on your computer... Usually a worm just uses ur computer as basically a server to spread as fast and silently as it can but others can have payloads attached to them, like a message box, or a deleting of certain files or shutdown of your computer, or just basically crashing your computer... Worms try to hide themselves as best they can(usually) but most of the time get caught really easily(look at blaster)

A virus once executed on your machine infects either com, exe or sys files or a combination of all three... Viruses are alot harder to get off your mmachine or even to get rid of... They have alot less spreading options then a worm does cuz viruses only infect files on ur machine... Usually viruses have a payload after infecting all files a certain number of files a certain time or date or just right after its infection takes place... These payloads differ but can be the same as the worms payloads or worse(i dont know wuts more worse then crashing sum1s machine but there must be much worse i guess)

Now this is pretty rare but sometimes there are combinations of the two.. A virus/worm combination can be EXTREMELY deadly. It can spread like wildfire through your machine and other machines upon which it can have payloads of crashing your computer or a network of computers while spreading to more computers.. There have been a select phew that do these tasks but there still are some out there and are very dangerous... Hope this helped a little bit