You may have been working with a printer and they start telling you all the paper options which you have to choose from. There as several types finishes and weights, so to help you a little, here is a list of common weights and the purpose of each..
20 lb bond/50 lb text
Most often found in your everyday copy machine.
24 lb bond/60 lb text
Generally multipurpose paper used in the office printer. Also the most popular business letterhead or stationary weight.
28 lb bond/70 lb text
Perfect weight for brochures and presentations. Excellent for 2-sided printing with minimal show through.
32 lb bond/80 lb text
Perfect weight for brochures and presentations. Excellent for 2-sided printing with minimal show through, while being slightly heavier than the 28lb.
100# Gloss Text A gloss sheet that is perfect for brochures, booklets or flyers. Gloss accepts varnishes and coatings to bring more durability or mirror finish to your project.
67 lb Bristol
Often considered the lightest of the cardstocks, great for self mailers with a flexible "soft feel" quick drying surface.
90 lb index
A durable cardstock with a smooth, hard surface for medium applications.
65 lb cover
A sturdy stock with a superb "soft feel" fast drying surface. Great for postcards, menus and posters.
90/110 lb index
Both 90 and 110lb index are the common weights for tabs, dividers and manila folders. The average weight of an index card for heavier applications.
80 lb cover
A heavy cardstock, your most conventional business card weight. Available in a wide variety of textures and finishes. This sheet is printed on 80lb cover.
140 lb index
For super heavy weight applications.
100 lb cover
A noticeably heavier cardstock often us
ed for flat cards or invitations.
A heavy weight paper that can come Uncoated / Coated 1 Side (C1S) or Coated 2 Sides (C2S). This is a heavy weight stock used for color business cards and postcards. Coated Stock accepts Varnishes and Coatings to make your card more durable and glossy.