Reminder Items

Question 1

Program

Answer 1

A list of Instructions for a computer to execute

Question 2

Data

Answer 2

Everything that is not an instr

Question 3

What does it mean to run the program?

Answer 3

executing program code instruction after instruction)

Question 4

Computer component that executes program?

Answer 4

CPU

Question 5

Running Program is stored here, what else is stored there?

Answer 5

RAM stores currently running programs and data of a program

Question 6

RAM

Answer 6

Random access means- it takes roughly the same amount of time to access a piece of data, no matter where this piece of data is stored physically on the memory device.
Volatile - once power supply is off all the data in RAM memory is erased.
Slow compared to the CPU.

Question 7

Memory Stall

Answer 7

an undesirable scenario when CPU pauses and waits for the necessary data to be delivered from RAM memory.

Question 8

Long-Term Storage?

Answer 8

Hard Disk- non volatile

Question 9

Executable File

Answer 9

An executable file is a file that contains machine code or bytecode that can be directly executed by the computer’s CPU or an interpreter without needing further compilation.

Question 10

How speed of CPU, RAM and hard disk compare to each other?

Answer 10

CPU, RAM Hard Disk fastest to slowest

Question 11

Cache Memory

Answer 11

special device between CPU and RAM, at acts as a buffer for a slower, larger memory. Between the CPU and RAM
- Speeds up interactions between CPU and RAM.

Question 12

ROM memory

Answer 12

READ-Only memory
a type of non-volatile memory that stores permanent data and instructions for a computer to start up and run.

Question 13

Machine Cycle

Answer 13

sequence of steps that the CPU takes to execute one single instruction.

Question 14

3 Steps Of Machine Cycle

Answer 14

Fetch command: retrieving next instruction from RAM memory and stores it in the program counter

Decoding: CPU decodes the instruction to determine what operation needs to be performed

Execution: CPU executes the instruction

Question 15

What Frequency measures? What is the measurement unit of frequency?

Answer 15

(Hz = times/second)
Measures CPU frequency or clock rate. How many cycles per second

Question 16

CPU Clock

Answer 16

a device (hardware) that issues synchronization pauses for all other CPU components.
When pause arrives, each component does one unit of WORK.

Question 17

CPU Frequency

Answer 17

CPU frequency is clock speed, measures how many cycles CPU can complete in one second.
Cycles/ seconds

Question 18

CPU Core

Answer 18

little CPU, each one is an individual processor.
our cores, allowing it to process four tasks (or threads) at the same time. (can boost performance w/ apps that are designed to utilize multiple CPU cores)

Question 19

How does memory look like

Answer 19

linear array of bytes

Question 20

What is byte? What is bit? How many bits are in a byte?

Answer 20

BYTE- 8 bits
Bit - Binary Digit in base 2 (either 0/1) they are components of info

Question 21

Memory Address

Answer 21

Specific bytes that refer to a specific place in RAM

Question 22

What is the memory address of a larger chunk of memory?

Answer 22

Typically expressed in hexadecimal

Question 23

Length of memory address

Answer 23

2^n where n= length of memory address

Question 24

How long should be memory addresses to address a given amount of memory?

Answer 24

log2 ( N) where n- given amount of memory in bytes

Question 25

Can memory contain nothing

Answer 25

NO, when the computer is powered on RAM stores information to prepare it for use.

Question 26

What is the relationship between C++ variable, RAM and memory address?

Answer 26

Variables are a high level construct that allows us to deal with RAM.
After compilation variables disappear from the program and turn into memory addresses that refer to a specific place in RAM.

Question 27

C++ pointer

Answer 27

a variable that stores the memory address of another variable

Question 28

C++ data types: char, short, int, long, long long, float, double? Does signed/unsigned affect those sizes (for example, is the size of int, signed int, and unsigned int equal)?

Answer 28

char: 1 byte (8 bits)
short: 2 bytes
int: 4 bytes (32 bits)
long: 4 bytes (32 bits)
long long: 8 bytes
float: 4 bytes (32 bits)
double: 8 bytes
Signed or unsigned does not effect size they are EQUAL.

Question 29

Hexadecimal numbers. Why do we use them? How to convert from hexadecimal to binary and back quickly?

Answer 29

A9
1010 1001

This is because memory is typically organized in byte-addressable units, and each hexadecimal digit represents four bits

Question 30

Word

Answer 30

is the amount of data that a computer can deal with in one operation. (usually mean 4 bytes)

Question 31

PC

Answer 31

Program Counter- stores the address of the next instruction to be executed

Question 32

language that the CPU understands

Answer 32

Machine Language -consists of binary instructions.

Question 33

How can we execute program written in higher-level languages?

Answer 33

High-level programming languages (e.g., C++, Python, Java) are translated into machine language via a compiler or interpreter, allowing the CPU to execute those instructions directly.

Question 34

Compiler

Answer 34

translates high level code into machine language through a final executable file. The executable can be ran over and over again.

Advantage - creates faster programs. Translates the entire program into machine code before execution begins. Once the program is compiled, the CPU can execute the machine code directly without any further translation.
Disadvanatge: Platform specific to the type of system arch.
Languages: C++, C, Rust

Question 35

Interpreter

Answer 35

An interpreter is a type of program that translates and executes code line-by-line rather than translating the entire program at once like a compiler. It reads a high-level programming language (e.g., Python, Ruby, JavaScript), converts each line into machine code, and executes it immediately.

Advantage: Platform Independence
Disadvantage: Programs generally run slower because translation happens every time the program is executed, rather than just once. Plus its needed every time code Is ran.
Interpreted languages: JS, Python, Java, C#