"MD5? Not much of a challenge"
~ Sherlock Holmes on MD5
"No shit, Sherlock!
~ Dr. Watson on the above statement.
MD5 is an algorithm designed to destroy data by making it unreadable by anyone, even yourself. Nowadays, however, MD5 is considered outdated and inferior to algorithms such as ROT13, for which no known decryption algorithms exist. MD5, on the other hand, is considered vulnerable because all those websites you use to actually get all these MD5 codes store them and can show the original phrases to anyone. An example is this website.
MD5 codes are easy to identify. When you see something like this:Nihilism, it usually stands for something. It is even rumored that supposedly "random" session IDs that PHP generates are in fact Satanic messages. This has been famously used by St. Ignucius as an argument against MD5, although the alternative he proposed, MD6, turned out to be even more controversial because of the number in its name.
edit Other applications of MD5
Many. Basically, MD5 is used whenever someone wants some hexadecimal gibberish. This is the context in which it was famously used by Eon8. Sometimes, system administrators use MD5 to generate real-looking databases with "secret" content and then give them away to hackers just to see them go nuts.
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