# Applications¶

The concept of "Software Application" is related to the main modeling engine and associated software tools employed by the user for the design, execution and postprocessing of a simulation Job, through the implementation of any of the available computational methods.

Each application may be comprised of one or multiple Executables, implementing in turn different possible computation Flavors. These settings can be entered within the unit editor interface of Workflow Designer.

## Executables¶

Applications are typically run via the launching of their respective executable binary files 1 (more simply referred to as Executables), of which there may be just one or multiple.

### Example¶

The Quantum ESPRESSO modeling application for example is comprised of several main input executables, included as part of its distribution package, such as pw.x, ph.x, bands.x etc.

Other applications such as VASP on the other hand contain just a single main executable, through which all of its supported computation features can be performed.

## Flavors¶

The executables for running modeling applications may in turn be composed of numerous distinct Flavors, implementing different forms and types of materials computations such as total ground-state energy calculations, structural relaxations or electronic bandstructure calculations.