A Level OCR Computer Science 2.1 - Elements of computational thinking Questions And Answers 100% Correct!

Define computational thinking - ANSWERSThe ability to think logically about a problem and apply techniques for solving it Define Abstraction - ANSWERSThe process of removing unneeded complexities, which creates a more generalised solution that is more useful. Reduces computational resources required. Focus on the main purpose of program What is the need for abstraction? - ANSWERSSaves memory and resources: Large amount of irrelevant data, that would prevent the most efficient and general solution being found Give some examples of abstraction (3) - ANSWERSReplacing complex objects with simple ones (like shapes) Removal of scenery Places can be represented by shapes with names Define thinking ahead - ANSWERSThe process of identifying the inputs, outputs and preconditions of a program What are the advantages of defining preconditions - ANSWERSMakes program components reusable, cuts out unnecessary checks, makes program easier to debug and maintain What is the need for reusable program components - ANSWERSSaves time and money, pre-written code will be well tested and bug free, inputs outputs and preconditions already specified Define caching - ANSWERSSaving Data and instructions that are frequently accessed in case they are needed again. Allows for faster access in future What are some advantages of web caching - ANSWERSFaster access to cached resources, saves use of bandwidth, reduces load on web server What are some disadvantages of web caching - ANSWERSMay cause user to view "stale" copies of the website, takes up space on the hard drive What are some programming standards - ANSWERSInputs outputs and preconditions should be documented, variable identifiers should conform to a standard convention, all variables should be local to the module, documentation should be in a standard format, code should be commented, no module one page What makes a problem solvable by computational methods **** - ANSWERSInvolves calculations, has inputs processes and outputs, involves logical reasoning Define thinking procedurally - ANSWERSThe process of identifying the subprocedures necessary to solve a problem Define decomposition - ANSWERSThe process of breaking done a larger problem into several smaller problems that are easier to solve Define structured/ modular programming - ANSWERSUses top-down analysis for problem solving, identifying major tasks and breaking them down into subtasks, Tasks and subtasks are written as separate, self contain modules using local variables, Uses selection iteration and sequence (structured code) Define modularisation - ANSWERSBreaking down of a program into several blocks of self contained code called modules What are the benefits of modularisation - ANSWERSPrograms are more reliable and have few errors, programs take less time to test and debug, programs are easier to maintain, modules can be reused, several programmers can work on the same program at once What is a system diagram - ANSWERSOne in which a program is broken down into its subprocedures which are then broken down into their subprocedures etc Define thinking logically - ANSWERSThe process of deciding and identifying where decisions should be or are made in a program Define decision points - ANSWERSPoints in a program where a decision is made based on a condition that affects the flow of a program How do decisions affect the flow of a program - ANSWERSDifferent decisions are made based on conditions. Different decisions case different outcomes, affecting the flow of the program