Collating
To arrange multiple pages in order (to be stapled or clipped, for example).

Creative
Direct marketing services usually offer creative services. Designers and copywriters will design and write a piece that fits your campaign. The creative refers to the actual mail piece, whether it be a postcard, brochure, or pamphlet.

First Class Mail
First class mail is more expensive than bulk mail, with cost increasing with each ounce. It allows for speedy delivery, and the post office takes extra care to make sure it's delivered to the right address, that it's returned to sender if an address is wrong, etc.

Fulfillment
The actual process of stuffing envelopes, setting up a mailing list, and shipping out a mailing piece. Following up on and tracking a mailing is also part of fulfillment.

Inserting
To place a piece into a direct mail package. Unlike nesting, it doesn't require the extra step of being placed in a specific location in the mailing piece.

Live Postage
A piece of mail is considered to have live postage when a postage stamp is affixed to a mailing piece, as opposed having the piece run through a postage meter.

Mailing List
A list purchased (or created from your own resources) containing addresses to which you'll send your direct mailing. You can purchase a list of random names or pay to have the list targeted to a certain type of person, a geographic area, an age group, etc. Lists can also be purchased for fax and email mailings.

Matching
To put a mailing piece together with a specific addressee - if, for example, a personalized letter needs to be matched to a specific address on an envelope.

Merge/Purge
To combine more than one mailing list (merge), and then delete any duplicate entries (purge).

Nesting
To place an insert within a direct mailing piece (for example, directions placed inside an invitation).

Permit/Metered Mail
An authorization stamp that deducts from a postage account the mailer has at the post office. This would be done instead of affixing a live stamp.

Sorting
Putting mail pieces in order by zip code.

Standard/Third Class/Bulk Mail
To qualify as bulk mail, there must be at least 200 pieces or 50 lbs. of mail. While first class postage increases with every ounce, standard mail gives you the same low rate of postage up to 3.3087 ounces. Delivery is slower.