Importance of surrogate key in Data warehousing

What is the importance of surrogate key in Data warehousing?

-Surrogate key will come into picture when dimension in a table is changing slowly

-Surrogate key can identify the changes made in various dimensions

-The three slowly changing dimensions are (1) SCD1, (2) SCD2 and (3) SCD3.

-Surrogate keys are generated by the system.

-The keys are the sequence numbers / alphanumeric values