edges sharp though edge split modifier not added Hello Blender Community,

I imported an OBJ mesh into Blender. When I set the shading to smooth some edges appear sharp and others don't, though I haven't added the edge split modifier.

If I go into Edit Mode I can see the blue lines indicating the sharp lines. I already checked if there are doubles by merging vertexes by distance and I checked if the normals are all pointing in the right direction.
Does anybody know what happened here?

Here's a picture of the object:

Here's a pictuer of the object in edit mode:
I've figured it out by myself now: In Properties > Object Data > Normals > Auto Smooth.
It's kinda like Edge split but not as an Modifier but it works the same, maybe even better.