Testimonials from customers who are not famous have been effectively used in marketing for as long as marketing has existed.[citation needed] A past or current customer will present a formal "word of mouth" testimonial that a business can use in marketing and to build trust with future customers. Testimonials are incredibly effective when believed to be true, but a challenge is having the audience believe that testimonials presented by a business are given by real people, not fabricated by the business itself. Even so, testimonials, reviews, and case studies are still considered by most marketing experts to be the most effective means of marketing and gaining brand trust by small- and medium-sized businesses. Testimonials have reached an all-time high in importance as the internet is now a plethora of reviews (synonymous with testimonials). Websites such as Yelp!, Google+, TripAdvisor, and many more have become 'go to' places for individuals who are seeking other customers reviews/testimonials about a particular business. To put the growth of this industry into perspective, for example, Yelp.com's growth alone can be noted: Yelp.com has more than 71 million monthly unique visitors as of January 2012. Instagram especially has increasingly been useful in distributing testimonials on products and places. It is done by making use of the tagging feature that directly links to the original brand or the particular location that the picture was taken. Moreover, the description of the pictures are also used to write either the review or sentences that compliments the product or place. Users with a large number of followers are commonly targeted for endorsement deal requests that aims to create these testimonial posts, where in return, the user receives commission for 'advertising' the place or product. However, it can only be called an endorsement deal when the company or label contacts the user directly to create such testimonial post, and the user receives commission. This is becoming a trend in Indonesia, especially amongst users with at least one thousand followers, where some are now known for posting pictures with advertising purposes