Haze and fog lead to image degradation by various degradation processes like image contrast, image blurring and pixel distortion. It has effected the efficiency of computer and machine vision algorithms. A number of single image and multiple image restoration based image defogging algorithms have aimed to solve the problem in an efficient and fast manner. The objective of the paper is to summarize present state of the art image defogging algorithms. Firstly, an image classification algorithm has been presented and then we summarized present state of the art image restoration based image defogging algorithms. Finally, we summarized image quality assessment methods followed by their comparisons of various image defogging algorithms. Problems of image dehazing and future scope have been discussed thereafter.