Software design is a(66)process. It requires a certain(67)of flair on the part of the designer. Design can net be learned from a book. It must be practiced and learnt by experience and study of existing systems. A well(68)software system is straight forward to implement and maintain, easily(69)and reliable. Badly(68)software systems, although they may work are(70)to be expensive to maintain, difficult to test and unreliable.