Explanation: Surface texture is the degree of finish conveyed to the machinist by a system of symbols devised by a Standards Association. These symbols provide a standard system of determining and indicating the surface finish. [ alt="RRB JE ME 57 15Q Metrology CH 1 Hindi - Final Diag(Deepak) images Q11" src="//storage.googleapis.com/tb-img/production/19/07/RRB_JE_ME_57_15Q_Metrology_CH_1_Hindi%20-%20Final_Diag%28Deepak%29_images_Q11.PNG"> Surface terms: Flaws: Flaws are random irregularities or scratches, holes depression, seams, tear, or inclusions. These are defects caused during the machining operation. Lay: It is the direction of the surface pattern caused by the machining and is visible to the naked eye. Roughness: Roughness is the irregular deviation of the surface. Roughness height: Roughness height, Ra is the deviation of the centre line. Roughness width: Roughness width is the distance between successive roughness peaks parallel to the nominal surface. Waviness: Waviness is the recurrent deviation form a flat surface, it is measured and described in terms of the surface between adjacent crests of the waves (waviness width) and height between the crests and valleys of the waves (waviness height). Standard symbol to represent surface texture: Specifications Marking Placement of maximum roughness width rating to right of the lay symbol [ alt="F1 M.J 9.5.20 Pallavi D6" src="//storage.googleapis.com/tb-img/production/20/05/F1_M.J_9.5.20_Pallavi_D6.png" style="width: 127px; height: 80px;"> Placement of roughness width cut-off [ alt="F1 M.J 9.5.20 Pallavi D7" src="//storage.googleapis.com/tb-img/production/20/05/F1_M.J_9.5.20_Pallavi_D7.png" style="width: 127px; height: 46px;"> Placement of minimum value roughness height [ alt="F1 M.J 9.5.20 Pallavi D8" src="//storage.googleapis.com/tb-img/production/20/05/F1_M.J_9.5.20_Pallavi_D8.png" style="width: 129px; height: 49px;"> Placement of maximum value of roughness height [ alt="F1 M.J 9.5.20 Pallavi D9" src="//storage.googleapis.com/tb-img/production/20/05/F1_M.J_9.5.20_Pallavi_D9.png" style="width: 131px; height: 46px;"> Placement of maximum waviness height and The maximum waviness width value [ alt="F1 M.J 9.5.20 Pallavi D10" src="//storage.googleapis.com/tb-img/production/20/05/F1_M.J_9.5.20_Pallavi_D10.png" style="width: 133px; height: 102px;">