A good example of this can be noticed in most supermarkets where instead of pricing at £10, it would be written as £9.99. Pay what you want is a pricing system where buyers pay any desired amount for a given commodity, sometimes including zero. In some cases, a minimum (floor) price may be set, and/or a suggested price may be indicated as guidance for the buyer. The buyer can also select an amount higher than the standard price for the commodity. Giving buyers the freedom to pay what they want may seem to not make much sense for a seller, but in some situations it can be very successful. While most uses of pay what you want have been at the margins of the economy, or for special promotions, there are emerging efforts to expand its utility to broader and more regular use. Penetration pricing includes setting the price low with the goals of attracting customers and gaining market share. The price will be raised later once this market share is gained. A firm that uses a penetration pricing strategy prices a product or a service at a smaller amount than its usual, long range market price in order to increase more rapid market recognition or to increase their existing market share. This strategy can sometimes discourage new competitors from entering a market position if they incorrectly observe the penetration price as a long range price. Companies do their pricing in diverse ways. In small companies, prices are often set by the boss. In large companies, pricing is handled by division and the product line managers. In industries where pricing is a key influence, pricing departments are set to support others in determining suitable prices. Penetration pricing strategy is usually used by firms or businesses who are just entering the market. In marketing it is a theoretical method that is used to lower the prices of the goods and services causing high demand for them in the future. This strategy of penetration pricing is vital and highly recommended to be applied over multiple situations that the firm may face. Such as, when the production rate of the firm is lower when compared to other firms in the market and also sometimes when firms face hardship into releasing their product in the market due to extremely large rate of competition. In these situations it is appropriate for a firm to use the penetration strategy to gain consumer attention. Predatory pricing, also known as aggressive pricing (also known as "undercutting"), intended to drive out competitors from a market. It is illegal in some countries. Companies or firms that tend to get involved with the strategy of predatory pricing often have the goal to place restrictions or a barrier for other new businesses from entering the applicable market.