Spam is the scourge of the Internet. It clogs inboxes, crashes servers, wastes time and money and is an abuse of privacy. More than half of the two trillion e-mail messages sent in 2006 are likely to be spam. According to the anti-spam Web site Spamhaus Project, about 200 spammers worldwide are responsible for about 80% of all spam in Europe and North America. There are an estimated 2,300 spammers in the US.
The short answer is "no", but it is a qualified "no" because there are odd ways of interpreting the question which could justify the answer "yes". Light is composed of photons so we could ask if the photon has mass. The answer is then definitely "no": The photon is a massless particle. According to theory it has energy and momentum but no mass and this is confirmed by experiment to within strict limits. Even before it was known that light is composed of photons it was known that light carries momentum and will exert a pressure on a surface. This is not evidence that it has mass since momentum can exist without mass. [ For details see the Physics FAQ article What is the mass of the photon? ]. Sometimes people like to say that the photon does have mass because a photon has energy E = hf where h is Planck's constant and f is the frequency of the photon. Energy, they say, is equivalent to mass according to Einstein's famous formula E = m
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