What does Canned Spam mean?

Canned Spam meaning in Urban Dictionary

never originally-written, long compositions of drivel slice and pasted into unsolicited email messages or posted to many other individuals web log commentary areas and / or to internet forums, particularly to numerous usenet newsgroups. Canned Spam generally attempts to help scientifically or politically outrageous world views. Utilize: Canned Spam is actually used by Loony Left,Wingnut, and Netkook kinds in false belief that many individuals would think as they do if only it might be explained properly.