writing simple programs create design formulate the overall structure of the program this is where the how of the program gets worked out the main task is to design the algorithm(sthat will meet the specifications implement the design translate the design into computer language and put it into the computer in this bookwe will be implementing our algorithms as python programs test/debug the program try out your program and see if it works as expected if there are any errors (often called bugs)then you should go back and fix them the process of locating and fixing errors is called debugging program during the debugging phaseyour goal is to find errorsso you should try everything you can think of that might "breakthe program it' good to keep in mind the old maxim"nothing is foolproof because fools are too ingenious maintain the program continue developing the program in response to the needs of your users most programs are never really finishedthey keep evolving over years of use example programtemperature converter let' go through the steps of the software development process with simple real-world example involving fictional computer science studentsusan computewell susan is spending year studying in germany she has no problems with languageas she is fluent in many languages (including pythonher problem is that she has hard time figuring out the temperature in the morning so that she knows how to dress for the day susan listens to the weather report each morningbut the temperatures are given in degrees celsiusand she is used to fahrenheit fortunatelysusan has an idea to solve the problem being computer science majorshe never goes anywhere without her laptop computer she thinks it might be possible that computer program could help her out susan begins with an analysis of her problem in this casethe problem is pretty clearthe radio announcer gives temperatures in degrees celsiusbut susan only comprehends temperatures that are in degrees fahrenheit nextsusan considers the specifications of program that might help her out what should the input beshe decides that her program will allow her to type in the temperature in degrees celsius and the outputthe program will display the temperature converted into degrees fahrenheit now she needs to specify the exact relationship of the output to the input susan does some quick figuring she knows that degrees celsius (freezingis equal to degrees fahrenheitand celsius (boilingis equal to fahrenheit with this information she computes the ratio of fahrenheit to celsius degrees as - - using to represent the fahrenheit temperature and for celsiusthe conversion formula will have the form + for some constant plugging in and for and respectivelysusan immediately sees that sothe final formula for the relationship is that seems an adequate specification