# What is “bpy.ops.object” really?

I'm a little confused about the structure of bpy.

Take bpy.ops.object.some_operation(), it seams to work on the selected object. Or is it the active object?

How about bpy.context.active_object, is that the same? Or what about bpy.data.collections['Collection'].all_objects or bpy.context.scene.collection.all_objects or bpy.context.scene.objects?

How do they exactly relate to objects in Blender?

I can't really find a clear description anywhere and it leads to my code sometime missfiring, even though seemed it has worked for me previously.

I know it's a noob question but I would really appreciate any clarification on the matter.