Alternatives are the building blocks behind scenarios. They are categorized data sets that create scenarios when placed together. Alternatives hold the input data in the form of records. A record holds the data for a particular element in your system.

Scenarios are composed of alternatives as well as other calculation options, allowing you to compute and compare the results of various changes to your system. Alternatives can vary independently within scenarios and can be shared between scenarios.

Scenarios allow you to specify the alternatives you want to analyze. In combination with scenarios, you can perform calculations on your system to see the effect of each alternative. Once you have determined an alternative that works best for your system, you can permanently merge changes from the preferred alternative to the base alternative.

When you first set up your system, the data that you enter is stored in the various base alternative types. If you want to see how your system behaves, for example, by increasing the diameter of a few select pipes, you can create a child alternative. You can make another child alternative with even larger diameters and another with smaller diameters. The number of alternatives that can be created is unlimited.