• Bump map:
  Bump mapping is a technique in computer graphics for simulating bumps and wrinkles on the surface of an object.
  
  
  • A material (ex. Lambert) > Attribute Editor > Common Material Attributes > Bump Mapping
  • Arnold Shader > Geometry > Bump Mapping
    
    
• Displacement Mat:
  With Displacement maps, depressions and elevations become part of the geometry of the object unlike Bump maps that only create the illusion of surface relief.
  
  
  • Go to aiStandardSurface tab > Click the box with right arrow

Click checker box then choose a texture like noise