Web caching replacement algorithms gained popularity and came into picture because of increasing demands of web documents.  As the load over the servers has increased so much that handling requests of the clients in large amount becomes difficult. To avoid this, proxy caches are used, which are burden reducers for the server. Caches occupy less amount of space and contain only those pages which are likely to be accessed by the clients. To increase the speed over the Internet or to fulfill the requirements of the client on timely basis, it is very important to strengthen the efficiency of replacement algorithms being used to replace those web documents from the cache which are not likely to be accessed in future and bring those documents which have higher probability of being accessed. Therefore, optimization of algorithms of replacement policies has become significant and a chief concern. The future scope is very vast in this area because Internet has become a predominant priority in every direction.