layer ve tier arasındaki fark nedir?Sadece örnek cümleler vermekten çekinmeyin.

In plain english, the Tier refers to "each in a series of rows or levels of a structure placed one above the other" whereas the Layer refers to "a sheet, quantity, or thickness of material, typically one of several, covering a surface or body".

Tier is a physical unit, where the code / process runs. E.g.: client, application server, database server;

Layer is a logical unit, how to organize the code. E.g.: presentation (view), controller, models, repository, data access.