DATA STRUCT

Main Memory (RAM)

Stores programs and data; volatile.

Volatile Memory

Loses data when power is off.

Cache Memory

CPU memory for frequently used data/instructions.

Bus

Transfers data between CPU memory and devices.

Register

Small fast storage inside the CPU.

Persistent Storage

Nonvolatile storage (e.g. HDD/SSD).

Virtual Memory

Uses storage to extend RAM capacity.

Data

Information stored and processed by programs.

Memory

Collection of transistors storing binary values.

Transistor

Electronic switch with ON/OFF states.

Binary Number System

Uses 0 and 1.

Numbering System

Method of counting and arithmetic.

Abstract Data Type (ADT)

Defines memory size and data type.

Short

Half the size of an int.

Int

Standard integer type.

Long

Double the size of an int.

Char

Stores a character.

Float

Stores decimal numbers.

Double

Larger and more precise decimal type.

Boolean

Stores true/false values.

Byte

8-bit integer.

Single Precision

Float precision up to about 7 decimal digits.

Hexadecimal

Base-16 numbering system (0-9 A-F).

Memory Address

Location of data in memory.

Data Type

Determines memory size and data stored.

Variable Name

Identifier for a memory location.

Semicolon (;)

Ends a statement.

Primitive Data Types

Built-in language data types.

User-Defined Data Type

Programmer-created type.

Structure (Struct)

Groups different data types together.

Structure Name

Identifier of a structure.

Structure Body

Members enclosed in braces.

Class Definition

Blueprint for creating objects.

Class

Represents an object's attributes and behaviors.

Attributes

Data members of a class.

Class Name

Identifier of a class.

Class Body

Contains attributes and methods.

Pointer

Variable that stores a memory address.

Asterisk (*)

Used to declare or dereference pointers.

Address Operator (&)

Gets the address of a variable.

Pointer Variable

Holds a memory address.

Pointer Arithmetic

Moving through memory using pointers.

Pointer to a Pointer

Pointer that stores another pointer's address.

Array

Collection of elements with the same name.

Array Element

Individual item in an array.

Index Value

Position number of an element.

Allocation

Reserving memory.

Multidimensional Array

Array with multiple dimensions.

Array of Pointers

Array whose elements are pointers.

Ampersand (&)

Returns a pointer/address.

Dereference (*)

Accesses value stored at an address.

Array of Pointers to Pointers

Array containing double pointers.

Referencing

Passing or storing an address instead of a value.

Stack

FILO data structure.

FILO (First In Last Out)

First item inserted is last removed.

Top

Position of the most recent element.

Push

Add item to stack.

Pop

Remove item from stack.

isFull()

Checks if stack is full.

isEmpty()

Checks if stack is empty.

Private Access Specifier

Accessible only inside the class.

Public Access Specifier

Accessible through objects.

Constructor

Function called when an object is created.

Industrial Strength

Robust reliable design.

Queue

FIFO data structure.

FIFO (First In First Out)

First item inserted is first removed.

Simple Queue

Processes items in order of arrival.

Priority Queue

Higher-priority items go first.

Priority

Importance value of an item.

Transaction

Information being processed.

Enqueue

Insert at back.

Dequeue

Remove from front.

Front

First element position.

Back

Last element position.

Size

Total queue capacity.

Circular Queue

Queue wraps around array.

Modulus Operator (%)

Used for circular behavior.

isFull() Queue

(back + 1) % size == front

isEmpty() Queue

back == front