The choice of a concrete mix depends on the need of the project both in terms of strength and appearance and in relation to local legislation and building codes.
The design begins by determining the requirements of the concrete.
Regular concrete is the lay term for concrete that is produced by following the mixing instructions that are commonly published on packets of cement, typically using sand or other common material as the aggregate, and often mixed in improvised containers.
The ingredients in any particular mix depends on the nature of the application.
In some applications of high-strength concrete the design criterion is the elastic modulus rather than the ultimate compressive strength.