Database Mirroring was initially implemented in Microsoft SQL Server 2005 as a go-to feature for many database professionals. Database administrators like using this feature to ensure their databases could be redundant and offer high availability. These particular attributes are desirable in an environment where five nines (99.999% uptime) is critical. Businesses need access to data around the clock for smooth operations, which makes high availability essential. More importantly, database mirroring has also been a key component in many disaster recovery plans.
Microsoft recently announced that SQL Server 2016 is the last version of the product that will support this feature. Database Mirroring is being deprecated and users are being asked to use Always On Availability Groups instead.
You can find out more about how to use Database Mirroring from Jay Dave here.