O'Reilly logo
  • Dustin Waybright thinks this is interesting:

The CASE expression has two forms—the simple form and the searched form.

From

Cover of Training Kit (Exam 70-461): Querying Microsoft® SQL Server® 2012

Note

The simple form does not allow for predicates in the WHEN clause whereas the searched from does allow for predicates and evaluates the return based on which predicate is returned TRUE.