BTL —
Below the line. An advertising technique to impact buyers that differs from direct advertising (ATL — above the line) and includes methods such as promotions to stimulate sales, merchandising, retail audit, events marketing and PR activities.
Marketing communications —
  1. Targeted interaction with customers and partners using media tools, including direct mailings, print media, TV and radio, billboard advertising and the Internet. A marketing communications campaign can use a single media source, but more often combines several approaches.
  2. Includes everything that supports brand promotion through marketing: advertising, PR, Internet, point-of-sale, print products, direct mailings, logo design, packaging, etc.
Public relations (PR) —
  1. Planned and sustained efforts to establish and maintain goodwill and strong relations between an organization and its target audience.
  2. Promotion and protection of a company's image.
Sales promotion —
A range of techniques used to attract consumers of goods and services, including discounts, coupons, warranties, gifts, contests, vouchers, demonstrations, prizes, bonuses and others; can be directed towards individual buyers (consumer promotion) or retail channels (trade promotion).