Bulk mail
The United States Postal Service defines bulk mail broadly as "quantities of mail prepared for mailing at reduced postage rates." The preparation includes presorting by ZIP code.
However, in common parlance, both bulk mail and junk mail are used to refer to advertising circulars, free trial CDs and other merchandising come-ons delivered by mail to homes and businesses. The term comes from the fact that in the majority of cases it is discarded without more than a cursory glance by the receiver. Advertisers often call it "targeted mailing", as mail is usually sent out due to database readings. For example a person who likes golf may get junk mail for golf related products.
Some people respond positively to bulk mail advertising and find useful goods and services on offer. Many, however, dislike or resent it, in the same way as with telemarketers' calls and e-mail spam and some jurisdictions like the US have laws requiring junk mailers to withhold their offerings from residents who opt out.
A stereotype commonly associated with junk mail is the misspelling of any but the simplest surnames. A famous example from the television series Friends is a letter that was meant for Chandler Bing but was actually addressed to 'Ms Chnadler Bong'.
An organization called the Mailing Preference Service allows people in the United Kingdom to register with them for free and they will ensure those people's addresses are removed from 95% of mailing lists.