# Features

## Covariance and Contravariance

* Covariance preserves assignment compatibility and contravariance reverses it.

## LINQ

{% content-ref url="features/linq" %}
[linq](features/linq)
{% endcontent-ref %}

## Asynchronous Programming

{% content-ref url="features/asynchronous-programming" %}
[asynchronous-programming](features/asynchronous-programming)
{% endcontent-ref %}
