Spelled
The most well-known of the classic grains is spelt. Spelt is considered the ancestor of wheat.
If spelt is allowed to rise for a long time, it develops a distinctive aroma. Spelt can be used instead of modern wheat for most types of baking. The reason why spelt has become so popular is due to both its aromatic qualities and also because it has a form of gluten that is more easily digestible for us humans compared to modern wheat. Many people therefore tolerate spelt better than modern wheat.
Sources
Organic specialty grains https://spesialkorn.no/kornarter-sorter/