# Type: Simple

> Simple activity type structure and generated code for activities that extend BaseAsyncCodeActivity without child activities.

## Activity Creator

![docs image](https://dev-assets.cms.uipath.com/assets/images/marketplace/marketplace-docs-image-35084-06f48208-7e7c9026.webp)

## Generated Code

Simple activities extend the `BaseAsyncCodeActivity`, which simply runs a bit of execution logic and creates the kind of activity seen below. These types of activities do not contain any child activities.

```
using ...
namespace MyCompany.MyProduct.Activities
{
    [LocalizedDisplayName(nameof(Resources.Addition_DisplayName))]
    [LocalizedDescription(nameof(Resources.Addition_Description))]
    public class Addition : BaseAsyncCodeActivity
    {
      ...
    }
}
```

## Effect in UiPath Studio

Simple activities may display fields in their designers. All required input properties are added to the designer.

![docs image](https://dev-assets.cms.uipath.com/assets/images/marketplace/marketplace-docs-image-33531-7f0029d1-27ca50d5.webp)