SQL Server replication is the process of copying and distributing data from one database to another, synchronizing the data between them to maintain integrity and consistency. It's a crucial feature in Microsoft SQL Server that enables creating multiple copies of a database for scalability, high availability, and reporting purposes. The key components involved in SQL Server replication include articles, publications, publisher databases, distribution databases, subscribers, subscriptions, subscription databases, agents, and distribution databases. There are four types of SQL Server replication: snapshot replication, transactional replication, peer-to-peer replication, and merge replication. Setting up a SQL Server replication involves preparing the environment, creating a distribution, creating a publication, configuring subscribers, initializing subscribers, starting replication, monitoring and maintaining the process, handling failures and conflicts. CData Sync simplifies the process of replicating a SQL Server by providing a user-friendly interface for configuring replication queries, scheduling jobs, and managing data integration. It supports continuous replication, incremental replication through CDC or row data, in-flight ETL and in-place ELT transformations, and seamless implementation in a matter of minutes.