Default Exports

A default export may signify a major, the most significant, or the only export a module may like to expose. Although a module can have zero or more named exports, it can have at most one default export.

Where to use default exports?

Use a default export if you have only one reference or class to export. Even when you have multiple things to export, you may use a default export if most of your module’s users use a particular reference more frequently than other ...