What are the road classifications?

It is not always clear how the street classifications are separated from each other. Here you can get an overview.

In Germany, roads are divided into different classes that reflect the area of responsibility and size. In the vialytics web app, a distinction is made between the common classes of federal roads, country roads, district roads, residential roads, access roads and side roads.
This distinction is based on the information tagged to the respective street in OpenStreetMap. More information about the distinction of streets can be found in this article. 

Federal road OpenStreetMap value: highway = primary  highway= primary_link
Country road OpenStreetMap value: highway = secondary,  highway= secondary_link
District road OpenStreetMap value: highway = tertiary highway = tertiary_link
Residential road OpenStreetMap value: highway = residential
Access road OpenStreetMap Wert: highway = service
Residential road OpenStreetMap value: highway = living_street
Side road OpenStreetMap value: highway = unclassified highway = track highway = road