SQL Server Replication vs SQL Server Backups

Complete the following:
Respond to the questions below, which addresses a crucial part of SQL Server, backups, and replication.
1. Define SQL Server Replication in 1-2 paragraphs
2. Define SQL Server Backups in 1-2 paragraphs
3. Compare and contrast the use of SQL Server Replication vs SQL Server Backups
4. Discuss how RAID will help in SQL Server Backups.