Internal turning is a hole enlargement process that is made by bringing pre-drilled or casting holes to certain dimensions. Boring is an extremely important and precise process in terms of hole tolerance, circularity and surface roughness. During internal turning besides cutting parameters, used cutting insert and used boring bar, has a direct effect on desired surface quality. In this study; The studies on internal turning process were collected. Obtained publications are discussed one by one, in terms of the effect of the boring bar (material, length-diameter (L/D) ratio, damping methods) and the insert (material, geometry, radius, coating) on the roughness of the machined surface, hole geometry, tool wear and cutting forces. As a result of the examinations, it was concluded that, the steel material boring bar is more economical, the carbide boring bar is better for machining holes with a larger L/D ratio, the vibration dampened bars, which are relatively new to use, being suggested that significantly reduce the cutting force, surface roughness and tool wear. Nevertheless, in the used inserts, it has been stated that those with small insert radius and positive cutting angles are more suitable for obtaining the desired hole geometry and tolerances, free surface and crater wear occurs, and better results are achieved on surface roughness and wear with coated inserts.