The digital world is engulfed by the imminent threat from digital perpetrators. Cryptography and authentication is necessary for digital communication to make sure that connecting parties are the authorized ones to have access to the exclusive data or information. It can be enforced by using cryptography and authentication algorithms. We present a study of the data threats and the role of symmetric and asymmetric key algorithms which may be used to circumvent such threats. A comparison is presented to identify the pros and cons of these algorithms. It is observed that these algorithms are still in a nascent phase and are improving gradually.