Md5 is a so-referred to as cryptographic hash feature. Even though md5 was to begin with designed to be used as a cryptographic hash feature, it has been observed to be afflicted by considerable vulnerabilities. It can still be used as a checksum to affirm information integrity, however simplest towards accidental corruption.
This essentially approach that you could provide in any bitstring as enter for the feature, and you may get out a fixed-size bitstring (128-bit inside the case of md5) as output. The output is typically called "digest".
The digest depends totally on the input and not anything else. For this reason in itself it may be used as an integrity proof, however no longer as authenticity, if the underlying hash feature has the important homes . Which means for 2 distinctive outputs the digest itself should be additionally different. The hassle is that the digest's size is constant, which in flip manner that with enough variety of messages it will always be possible to discover a collision (i.E., exceptional inputs yielding the equal output).
One must additionally note that there may be in recent times no justification to apply md5, as weaknesses had been discovered (namely post-restoration collision attacks). Additionally the usage of sha-256/512 on present day hardware is usually faster then md5.