2.5 New

Question 1

What is a low level language

Answer 1

A programming language that directly translate to machine code understood by the processor, allowing direct control over hardware components

Question 2

Features of low level languages

Answer 2

-directly translates to machine code
-allows direct control over hardware
-written for specific processors to ensure they embed the correct machine architecture
-does not closely resemble a natural human language, making it harder for humans to understand and write in
-executes more quickly

Question 3

Why are low level languages used

Answer 3

-when programmers need to write code that interacts directly with the hardware, such as device drivers
-when a program must be executed quickly

Question 4

Machine code (first generation) features

Answer 4

-pure binary code that computers can directly process and execute
-tedious and difficult for humans for humans to understand and write this
-can be used when a programmer needs to perform a very specific command that cannot be done in high level language
-executed faster because it is in a format the CPU can execute and does not need to be translated

Question 5

Features of assembly (second generation language)

Answer 5

-uses specialised command mnemonics to perform actions
-easier to understand and spot errors than machine code
-faster to execute than high level languages and can be used to directly control the CPU
-needs to be translates to machine code for the computer to execute it (one assembly instruction = one machine code instruction)

Question 6

Advantages of high level languages

Answer 6

-complete control over the system components
-occupy less memory and execute faster
-direct manipulation of hardware

Question 7

Disadvantages of low level languages

Answer 7

-difficult to write and understand
-machine dependent
-more prone to errors
-knowledge of computer architecture is key to program effectively

Question 8

What are high level programming languages

Answer 8

Programming languages that use English like statements to allow users to program with easy to use code

Question 9

Features of high level languages

Answer 9

-code that is similar to natural human language, easy to understand and use
-fewer errors and more powerful and complex commands than low level languages
-must be translated into machine code before it can run
-one instruction translates into many machine ode instruction
-clear debugging and programs are easier to maintain
(Needed due to development of processor speeds and increase in memory capacity

Question 10

Advantages of high level programming languages

Answer 10

-Easier to read and write
-easier to debug
-portable(can run on different types of hardware) so can be used on any computer
-one line of code can perform multiple commands

Question 11

Disadvantages of high level programming languages

Answer 11

-user is not able to directly manipulate the hardware
-needs to be translated to machine code before running
-program may be less efficient

Question 12

What is a translator

Answer 12

A program that changes (translates) program source code into machine code so that it can be executed directly by a processor

Question 13

what difference is there in the translation of high level languages and low level languages

Answer 13

-low level languages are translated using an assembler
-high level languages are translated using compilers or interpreters

Question 14

interpreter

Answer 14

converts high level languages one line at a time into machine code and executes it

Question 15

compiler

Answer 15

converts high level language into machine code for execution at a later time. The entire program is converted at once

Question 16

how do interpreters translate and execute code

Answer 16

-an interpreter translate source code (high level code) into machine code one line at a time
-must be reinterpreted every time the program is run
-can run and be edited without translating the whole program

Question 17

how do compilers translate and execute code

Answer 17

-a compiler translates all the source code into machine in one code
-produces an executable file that will run on other machines without the compiler needing to be installed
-only need to be translated once
-compiled programs have to recompiled after any changes are made

Question 18

how do interpreters report errors

Answer 18

-the interpreter would encounter the errors and report it to the user immediately and stops the program from running

Question 19

how do compilers report errors

Answer 19

the compiler analyses the entire program, taking note of where errors have occurred and records them in an error file, before it is run

Question 20

difference in complexity of compiler programs and interpreter programs

Answer 20

-interpreters are smaller, simpler programs
-compilers are larger, complex programs

Question 21

difference in execution speed of compilers and itnerpreters

Answer 21

-interpreters are slower as the code must be reinterpreted each time the program is run
-compilers produce more efficient code that interpreters making the compiled programs run faster, also do not have to be recompiled every time it is run

Question 22

advantages of interpreters

Answer 22

-instructions are executed as soon as they are translated, requiring less RAM
-stops when a syntax error is found, errors spotted easily, easier to debug

Question 23

disadvantages of interpreters

Answer 23

-slower execution
-must be translated every time it is run
-code is not optimised
-no executable file that can be distributed, source code must be supplied which can be modified without permission

Question 24

advantages of compilers

Answer 24

-faster execution, code already translated
-optimises the code, less RAM and time
-executable file can be distributed, source code will not be seen

Question 25

disadvantages of compilers

Answer 25

-more memory as whole source code needs memory -difficult to debug: does not spot errors, program must be compiled and run before errors can be seen -source code must re-compiled every time programmer changes the program -designed for one specific processor

Question 26

what are IDEs

Answer 26

software designed to make writing high level languages more efficient

Question 27

features of IDEs

Answer 27

-editor -compilers and interpreters (translators) -error diagnostics -run-time environment

Question 28

what is an editor

Answer 28

software that allows a programmer to enter and edit source code

Question 29

features can editors provide

Answer 29

-formatting tools (automatic indentation and changing font and format of word) -colour coding -statement completion -commenting code -line numbering

Question 30

errors diagnostics description

Answer 30

-tools that help to identify, understand and fix errors in code -such as identifying errors, debugger, line number of error

Question 31

run time environment description

Answer 31

gives users the ability to run and see the corresponding output of a high level language

Question 32

translator description for IDEs

Answer 32

built in to compile or interpret code without the need for extra piece of software

Question 33

Difference between compilers and interpreters

Answer 33

-compilers translates all the code in one go, interpreters translates one line at a time -compilers create an executable, whereas an interpreter does not, executes one line at a time -compiler reports all errors at the end, an interpreter stops when it finds an error

Question 34

Types of defensive design

Answer 34

-Input sanitation -validation -verification -authentication -maintainable code TESTING IS NOT INCLUDED