This is a broad-based area but its aim is to convince a consumer to try out a product or service. It can be as simple as putting an item before shoppers in easy to see places, like grocery stores do with magazines, gum, and candy bars. As long as you're standing at the checkout counter, your attention is up for grabs and a catchy display is one means of attracting it. This type vehicle has applications for resellers, if you select the right venue. Computer stores are frequently willing to allow online entrepreneurs to post brochures or discount coupons; in return, the stores might get a commission for referrals.
Companies often use free samples, discounts on an initial purchase, or a period of time during which the product can be used free of charge with no obligation as a means of luring consumers into trying items. And, giveaways don't necessarily have to be the product itself. Many companies have a store of promotional items with their logo imprinted on them, like t-shirts, coffee mugs, pencils, or mouse pads. This is (almost) free advertising in that your company's name will be put before other people and your only expense is production cost.
Promotions can also be done in a more pro-active manner through appearances at trade shows or professional expos. Virtually every community has some type business fair during which companies rent a booth and hand out informational material about themselves with a representative or two on hand to answer questions.