Prototyping
Prototyping is a means of exploring ideas before an investment is made in them. Depending on the scope of the prototype and the level of detail required, prototypes can be built at any time during the project. Sometimes they are created early in the project, during the planning and specification phase, commonly using a process known as breadboarding; that's when the need for exploration is greatest, and when the time investment needed is most viable. Later in the cycle packaging mock-ups are used to explore appearance and usability, and occasionally a circuit will need to be modified to take these factors into account.
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