When comparisons were initially made between the Apple Newton and the original Palm Pilot, two of the most striking differences were size and input.

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For example, in a traditional schools procurement an "input" approach is taken - the authority would specify the number and size of classrooms, the size of the dining area and games hall.

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People can input criteria such as their budget, how often the grocery shopping, desirable nutrition intake, size of the family, location, etc.

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