Evergreen content is just like it sounds; it is content that never goes away. So, follow along in this tutorial to learn more about Evergreen Content: the Ultimate Guide to Writing it.
The best example of evergreen content I can think of is a dictionary. Of course, there are always new words added to the English language in our day and age, but that does not mean that we stop looking up the meanings of older words. Likewise, people will always look up words they do not know because there is a chance one might come across them at some point in their life.
So, if you can think of a way to create evergreen content, then you're doing something right.