Programming

Question 1

What is a variable?

Answer 1

A named space in memory large enough to store a single data type

Question 2

What is a constant?

Answer 2

A named space in memory with a value that never changes while the program is running

Question 3

What are the 5 data types?

Answer 3

Boolean
Character (not in python)
Integer
Real
String

Question 4

What is declaration?

Answer 4

Code that causes a variable to exist

Question 5

What is assignment?

Answer 5

The process of putting a value into a variable

Question 6

What is the difference between definite and indefinite iteration?

Answer 6

Indefinite iteration is iteration using while loops and so carries on idefinitely till the conditional statement

Definite iteration is iteration using for loops and so is used a set number of times initially specified

Question 7

What are operations? What are the 3 types?

Answer 7

Operations are an action performed on one or more pieces of data in order to produce additional data

Arithmetic (+, -, *, /)
Relational (<, >, ==, !=)
Logical (and, or, not)

Question 8

What are the two types of data structures and their differences?

Answer 8

One-dimensional arrays store same data types with each element referenced by an index number

Two-dimensional arrays store same data types in a grid referenced by row then column

Question 9

What is a record?

Answer 9

A data structure that can accept multiple data items of different types. A row in a database

Question 10

What is an input and output?

Answer 10

Input is the process of introducing data to a system
Output is the process of communicating data beyond the system

Question 11

What is a file?

Answer 11

A store of data that continues to exist when the program or computer is no longer running

Question 12

What are the 6 string handling operations?

Answer 12

Concactenation
Length
Index
Substring
Convert
Conversion

Question 13

What does ord() and chr() do?

Answer 13

Ord() converts a character to ASCII
Char() converts an ASCII code to a character

Question 14

What is a subroutine?

Answer 14

A small subsection of the whole program that performs a specific task.

Question 15

What are the benefits of a subroutine?

Answer 15

Each subroutine can be give to a different programmer inviting teamwork
Subroutines can be separately tested without waiting for the whole program to finish
Subroutines that are commonly used can be reused

Question 16

What is a parameter and calling?

Answer 16

A piece of data that is passed into a subroutine in order for the subroutine to do its job.
Calling is a process where an instruction tells another named part of the code to run

Question 17

What is the return command in a function?

Answer 17

A command in which a subroutine passes a piece of data back to the line of code from which it was called

Question 18

What is modularisation?

Answer 18

The process of breaking a program into smaller parts called modules

Question 19

What is a robust program?

Answer 19

A robust program continues to function even when confronted with unexpected events, such as a lost network connection or user inputting data the wrong data type

Question 20

What is secure programming?

Answer 20

A secure program prevents users from accessing or altering data that they should not access or alter. Usernames and passwords make up one approach for keeping a program secure

Question 21

What is a validation algorithm?

Answer 21

Ensuring that data entered into the computer is reasonable and sensible.

Question 22

What is a range check?

Answer 22

Ensuring that data entered is within a specific numerical value range

Question 23

What is a type check?

Answer 23

Ensures that the correct data type has been entered

Question 24

What is a length check?

Answer 24

Ensures that a string contains a valid number of characters

Question 25

What is a lookup check?

Answer 25

Checks that what the user has entered exists on a list

Question 26

What is a presence check?

Answer 26

Simply checks that the user has entered something

Question 27

What is authentication?

Answer 27

The software process ensuring that the person accessing a system is the person who is supposed to access that system

Question 28

What is normal test data?

Answer 28

Data that is valid and that represents how the program would be used

Question 29

What is boundary test data?

Answer 29

Data that is just barely valid to check that the extreme ranges of normal input work correctly. Sometimes its good practice to test data that is just outside the acceptable range

Question 30

What is erroneous data?

Answer 30

Data that should not be accepted by the system. This is included to test to see whether a programs validation and error messages work correctly

Question 31

What is a high level programming language?

Answer 31

High-level languages are more understandable so high-level languages are far more popular

Question 32

What is a translator?

Answer 32

A program that translates source code into machine code

Question 33

What are the 3 types of translators?

Answer 33

Assemblers translate assembly language
Interpreters translate high level code one line at a time
Compilers translate an entire high level program at once before executing

Question 34

What are the advantages and disadvantages of an interpreter?

Answer 34

+ A program that contains errors can still be run till the error
+ Debugging is easier
- Every time it is run it needs to be interpreted
- Easier for unauthorised people to access source code

Question 35

What are the advantages and disadvantages of a compiler?

Answer 35

+ A compiled code will run quicker than reinterpreted code
+ It is more difficult for unauthorised people to access
- More memory used in compilation
- Entire program needs to be error free before