Difference Between DDA Line Drawing Algorithm and Bresenhams Line Drawing Algorithm.

Digital Differential Analyzer
 Line Drawing Algorithm		 Bresenhams Line Drawing Algorithm
Arithmetic
 DDA algorithm uses floating points i.e. Real Arithmetic. Bresenhams algorithm uses fixed points i.e. Integer Arithmetic.
Operations
 DDA algorithm uses multiplication and division in its operations. Bresenhams algorithm uses only subtraction and addition in its operations.
Speed
 DDA algorithm is rather slowly than Bresenhams algorithm in line drawing because it uses real arithmetic (floating-point operations). Bresenhams algorithm is faster than DDA algorithm in line drawing because it performs only addition and subtraction in its calculation and uses only integer arithmetic so it runs significantly faster.
Accuracy & Efficiency DDA algorithm is not as accurate and efficient as Bresenham algorithm. Bresenhams algorithm is more efficient and much accurate than DDA algorithm.
Drawing DDA algorithm can draw circles and curves but that are not as accurate as Bresenhams algorithm. Bresenhams algorithm can draw circles and curves with much more accuracy than DDA algorithm.
Round Off DDA algorithm round off the coordinates to integer that is nearest to the line. Bresenhams algorithm does not round off but takes the incremental value in its operation.
Expensive DDA algorithm uses an enormous number of floating-point multiplications so it is expensive. Bresenhams algorithm is less expensive than DDA algorithm as it uses only addition and subtraction.