immutable/mutable aliasing

[Jet via Digitalmars-d-learn]

There, how to distinguish between const and immutable? thank 
you~:)

/**
"Const types are like immutable types, except that const forms a 
read-only view of data. Other aliases to that same data may 
change it at any time. "

"Any data referenced by the const declaration cannot be changed 
from the const declaration, but it might be changed by other 
references to the same data. "
**/

Can sample code, please?