Week 3

Question 1

What is software?

Answer 1

A set of instructions that tell tell the hardware what to do. Created through the process of programming.

Question 2

What are challenges that can be solved by operating systems?

Answer 2

• Disk fragmentation;
• Limited memory;
• Concurrent processes;
• Compatability;

Question 3

What are distinctions within application software?

Answer 3

• Funtional Perspective
• Hierarchical perspective
• User perspective
• Data perspective

Question 4

What is meant by distinction functional perspective?

Answer 4

Divide them based on the function they have, for example for marketing or for logistics

Question 5

What is meant by the distinction hierarchical perspective?

Answer 5

• Divde them in software that is used for operational purposes or for managerial purposes or strategic purposes

Question 6

What is meant by the distninction user perspective

Answer 6

Divide them in terms of what kind of users are using the platform

Question 7

What is meant by the data perspective?

Answer 7

Data is core of information systems. So you divide the applications based on what the data is used for. Handling the present (transactions) or preparing for the future (analytics) or remembering the past (data warehouses)

Question 8

What is cloud computing?

Answer 8

• Use of internet for pooling IT resources.
• There is dynamic IT resource use and payment (so you give up your own IT center and use external parties for it).
• You pay for what you actually use;
• Virtualization and GRID
• Can be public or pricate

Question 9

What is virtualization

Answer 9

A server can run a 1000 users at the same time as they virtualize machines (so not real machines, but virtualized)

Question 10

What is GRID?

Answer 10

A thousand machines acting as one machine to improve performance

Question 11

What are three types of cloud computing?

Answer 11

• Software as a service (SaaS)
• Platform as a service (PaaS)
• Infrastructure as a service (IaaS)
• > in practice often combinations

Question 12

What is SaaS ?

Answer 12

Often what users see. So an application in the cloud. THink about your email

Question 13

What is PaaS?

Answer 13

Specically for developers. Like amazon webservices, provides a complete environment for development purposes

Question 14

What is IaaS?

Answer 14

Often for IT managers. Only gives you an basic structure, like a windows envirnment. You use it to run your own applications on top of it.

Question 15

What are advantages of Cloud Computing?

Answer 15

• You don’t have to store software yourself
• Available from every computer with internet access
• Large quantities of users can use it
• Services can be leased for as-need basis
• Your information is backed up externally
• New applications run and install quicky

Question 16

What are disadvantages of Cloud Computing?

Answer 16

• Information is stored at a server of someone else.
• Must have internet access
• Relying on third party

Question 17

What are the economic advantages of cloud computing?

Answer 17

• Low entry barriers
• Scalability
• Innovation is done for you
• Reduction of capital expenses and overhead

Question 18

What is open source software?

Answer 18

The source code is visible for the users and they can edit/modify it.

• Typically by programmer communities
• Typically free, but not necesarilly

Question 19

What is an advantage of Open source software?

Answer 19

• It is usually cheaper;
• Might be a big community that can help you if you are having problems
• Users can be used to make improvements

Question 20

What is an disadvantage of open source software?

Answer 20

• There is no provider that is responsible for it if you have problems

Question 21

What is the business model of open source software?

Answer 21

• TO an extent it is for fun by hackers and programmers, so no business model;
• Some companies focus on open source, so when they gain a lot of users these users might need consultancy services or machines

Question 22

What is modularization?

Answer 22

• Breaking programs up in parts so that a large program is easier to read and debug;
• It enables that parts of the program can be used in other programs

Question 23

What are the key ideas of modularization?

Answer 23

• Breaking up the program in parts that have a well-designed interface;
• Interface hides the internal structure of the module;
• The interface gives guidance on how to use that module;
• Interface is a stable reference point on how to evolve both the interface as the internal structure;

Question 24

What is the most important modularization paradigm?

Answer 24

• Object-oriented programming

- > with service-orientation as an extension

Question 25

What is object-oriented programming?

Answer 25

• Giving structure to a program so that properties and behaviours are bundled into objects;
• Model concrete, real-life things (cars, relations, employees) into software objects.
• Real world objects are the center in the programming (the grouping criterion) and in the overall structure of the program.

Question 26

What are the key items in object oriented programming?

Answer 26

• Class -> category/object
• instance -> what or who belongs to a class
• inheritance -> a subclass having all the properties of a class (but can have more)

Question 27

What is procedural programming?

Answer 27

• Structuring your program like a recipe, providing steps in the form of code blocks that carry out tasks to complete a task.