Amazon ElastiCache is a fully managed in-memory cache service that is compatible with the Redis and Memcached cache engines. ElastiCache allows you to store and retrieve data from a cache in memory, improving the performance of applications that require frequent access to data.

Creating an ElastiCache: 
● Open the AWS Management Console and navigate to the ElastiCache dashboard. ● Click the "Create cache cluster" button. 
● Select the cache engine and version you want to use (e.g. Redis, Memcached). ● Choose the cluster mode and number of cache nodes. 
● Select the cache node type and cache parameter group. 
● Choose the availability zone and VPC for your cache cluster. 
● Specify a cache cluster identifier and a cache cluster security group. ● Review and create the cache cluster. 
Your ElastiCache cluster should now be created and ready to use. You can view and manage your cache cluster in the ElastiCache dashboard, and modify its settings as needed. 
To connect to your ElastiCache cluster, you will need to obtain the cluster's endpoint and port. You can use the ElastiCache client libraries or the command line interface (CLI) to connect to your cache cluster from your application.