Different relational database engines are available (e.g. MySQL, PostgreSQL, SQL Server, etc), including Amazon's own Aurora.
RDS is optionally multi-AZ, which is only used for disaster recovery. Faults on the primary mean the secondary automatically becomes the primary. Note that this doesn't increase performance, it's for disaster recovery only. Performance can be increased with read replicas [[20220131032436-aws-rds-read-replicas]]. AWS handles the replication for you, so any writes happen on both.
Automated backups are possible
RDS are generally used for online transaction processing (OLTP), not online analytical processing (OLAP) OLTP - processes data from transactions in real time. Large numbers of small transactions OLAP - complex queries to analyse historical data. Large amounts of data.