may i know about ref cursor?.

Cursors allow you process the resultset row by row.
Advantage of cursors it improve the query performance.

1. This is a dynamic cursor which can holds multiple value at run time
2. Actually this is nothing but a data type of cursor variable

Ref cursor is basically a data type. A variable declared based on that data type is called cursor variable. The main advantage of using this variable is we can dynamically assosiate with different  queries at runtime depending upon  our requirement.