Search Engine Hated Techniques

There are some tact that are considered spam or called spamming techniques being used by spamer.

Mirror Sites/duplicate content / Duplicate Sites
Javascript Redirects Doorway pages
Dynamic Real Time Page Generation
Keyword stuffing and Page Swapping
Link stuffing and Link Farming
DHTML laying and Hidden text
Links inside No Script Tags
Use irrelevant Keywords
Use duplicate Domains
HTML invisible cells
Use Domain Spam
Redirects