how many type of defect in printing line plz explain in brief.?

Answer 1

Would have been nice if you were more precise or complete:
Printing line as part of assembly or packaging,
Printing line as in printing a document
Printing line of text in lead line typesetting.
Generally printing can be skewed (tipped on the page or package), shaded (lighter in one part than another), out of register (colors do not align with each other or with black), double printed (the material comes away and then recontacts the print face). With a lead typesetting, additionally the line can be broken - the first part does line with the second - the justification can be wrong spacing or wrongly placed, and a line can be placed upside down.