An email newsletter is a type of subscription-based communication where subscribers receive messages or updates from a particular sender on a periodic basis. The most common types of newsletters are those that provide news, updates, and commentary about a specific topic.
Some people use newsletters as an easy way to stay up to date on the latest news and developments in their industry or field. Others use them as a way to promote their own products and services to a wider audience.
Some people think of newsletters as a form of spam, while others see them as an important way to connect with potential customers. Ultimately, it depends on the specific goals of the newsletter publisher and the subscribers themselves.