Software Development: Languages and Environments

Question 1

Name 4 types of programming languages

Answer 1

• Procedural
• Declarative
• Event-Driven
• Scripting

Question 2

What is a Procedural language? (2) Give an example of a Procedural language (1)

Answer 2

• Procedural languages have a clearly set start and end point to the program
• The program follows a pre-defined pathway through the instructions to solve the problem
• Pascal is a Procedural language

Question 3

What is a Declarative language? (2) Give an example of a Declarative language (1)

Answer 3

• A Declarative language allows the programmer to create a knowledge base which contains facts and rules about a problem.
• A query is then used to interrogate knowledge base and draw conclusions
• Prolog is a Declarative language

Question 4

What is an Event-Driven language? (2) Give an example of an Event-Driven language (1)

Answer 4

• An Event-Driven language does not have a specific pathway in which the program instructions are executed
• Different parts of the program are evoked by events that take place during the running of a program, such as the user clicking on a command button
• Visual Basic is an Event-Driven language

Question 5

What is a Scripting language? (2) Give an example of a Scripting language (1)

Answer 5

• Scripting languages are provided with an application package to allow the user to go beyond the features available in the application
• They allow an expert user to customise the package and can be used to automate repetitive tasks
• Javascript is a Scripting language

Question 6

Name 2 features of a Scripting language

Answer 6

• They allow new functions to be added to existing software.

* They can automate repetitive tasks or operations

Question 7

What is a Macro?

Answer 7

A Macro is a set of actions performed by the user that have been recorded and can then be played back when required

Question 8

What are 2 benefits of using a Scripting language?

Answer 8

• To allow users to extend the functionality of an application
• To increase productivity through use of macros, which automate repetitive tasks

Question 9

What is a Compiler?

Answer 9

A Compiler is a translator that translates the entire source code into machine code before a program is run

Question 10

What is an Interpreter?

Answer 10

An Interpreter is a translator that translates source code one instruction at a time and executes it when the program is run

Question 11

What is an advantage of using a Compiler over an Interpreter? (2)

Answer 11

• Compiled programs run fast, as it has been translated before it’s run
• Interpreted programs run slower, as time is taken to translate code when the program is running

Question 12

What is an advantage of using an Interpreter over a Compiler? (2)

Answer 12

• Interpretors highlight errors immediately as it only translates one instruction at a time
• Compiled programs have to be compiled again before being run and tested if an error occurs

Question 13

What is a module library?

Answer 13

It is a collection of pre written subroutines that are available to a programmer to speed up the software development process

Question 14

What are 2 advantages of using a module library?

Answer 14

• Time is saved in not having to write the same programming code over and over again
• The module will have been pre tested, so will be free from errors

Question 15

What 2 pieces of documentation will there be in modules from a module library?

Answer 15

• A description of the function of the module

* The parameters that are passed in and out of the module and their data types