A data warehouse is a specialized type of relational database, optimized for analysis and
reporting of large amounts of data. It can be used to combine transactional data from
disparate sources making them available for analysis and decision-making. Amazon Redshift is
a managed data warehouse service that is designed to operate at less than a tenth the cost
of traditional solutions
Amazon Redshift achieves efficient storage and optimum query performance through a
combination of massively parallel processing (MPP), columnar data storage, and targeted data
compression encoding schemes. RedShift is particularly suited to analytic and reporting
workloads against very large data sets
Amazon RDS (and Aurora, which is an RDS DB), is a relational, transactional DB not a data
warehouse
Amazon DynamoDB is a NoSQL DB used for transactional systems also