Ciphers from the Modern Era
Modern algorithms are those that are used in current technology e.g. block ciphers, public key cryptosystems etc. These alogrithms are very secure (otherwise they would not be used), but in many cases we can practice on weakened versions of the algorithms.
These alogrithms are very secure (otherwise they would not be used), but we can practice on weakened versions of the algorithms in most cases.