LANGUAGES AND ENVIRONMENTS Flashcards
What does machine code consist of?
two characters 1 and 0
What is the language called that directly controls a computer?
A Low level Language
What is the name of the programming languages humans find easier to use?
High level languages
What must be done to a high level language before a computer can use them?
Must be translated into binary
What does syntax refer to?
The grammatical rules of a language
What are the three basic control structures used to control a computer?
- Sequence
- Selection
- Iteration
What do all three control structures mean?
- Sequence - any set of commands will be executed one after the other
- Selection - which command to execute depends on whether a condition is true or not
- Iteration - a set of commands is repeated for a set number of times, often called a loop
What does a program being problem oriented mean?
When a program is created to solve a particular sort of task or written with set people in mind
What are the four main types of programming languages?
- Procedural
- Declarative
- Object Oriented
- Domain Specific
Explain a Procedural language?
- Commonest Type of language
- Contains a set of commands that will be executed one after the other
- Designed originally to teach programming
- Use standard arithmetic operations
Explain Declarative Programming languages?
- Created to match how humans think
- associated with artificial intelligence programming
- Consists of a set of facts and rules (Knowledge base)
- Program run by entering a query, solution found by finding a match between the query and the rules and facts in the knowledge base.
- Will not necessarily follow a set of operations
A Declarative Programming language makes use of recursion, what is this?
recursion is when a sub program repeatedly calls itself until a simple base fact is identified.
A Declarative Programming language uses self modifying code, what is this ?
This is where the program modifies the set of facts and rules
What is an Object Oriented Language
This is a more efficient procedural language
What are objects
Objects are re-usable blocks of code which define data used within that block and how that data can be changed.
What do you call the data associated with an object
Instance variables or attributes
What are the procedures and functions that can change data called
methods or operations
How are errors by global variable less likely in an object oriented programming language
Objects are closed systems which cannot be altered from outside also known as encapsulation
what is meant by inheritance
this is the ability to create a sub class from a pre defined class
How do objects interact with each other
they send messages from one object to another
What are class libraries
these are sets of classes that can be used by developers as building blocks for complex applications
What type of language is designed with one specific task in mind
Domain specific
What is a scripting language
A scripting language is designed to add extra functionality to, or automate an application program or an operating system.
What is a macro
A macro is a sequence of operations that can be invoked as a single task
What are the two types of translators
Compilers and interpreters
Explain an interpreter
Line By line translation, Can identify errors immediately, need every time the program is run.
Explain a compiler
Translates all code at once, translation is saved no need to be translated again, more efficient as no extra memory or processor resources are needed.
