CSC 101 FINAL EXAM REVIEW

What is computer science mainly about? What is an algorithm?

Computer science is the study of algorithms and problem solving. An algorithm is a step-by-step set of instructions that solves a problem.

What makes an algorithm valid?

It must be ordered, unambiguous, computable, produce a result, and stop in finite time.

What are the 3 main algorithm operations?

• Sequential → steps in order

• Conditional → decisions

• Iterative → repetition/loops

What is an infinite loop and a computing agent?

An infinite loop never stops running. A computing agent is whatever carries out the algorithm (computer, robot, human, etc.).

Key people/events in computer history?

• Napier → logarithms

• Pascal → Pascaline

• Jacquard → punched cards

• Babbage → Difference & Analytical Engines

• ENIAC → early electronic computer

• von Neumann → stored-program architecture

Why do computers use binary?

Electronics work reliably with two states: on/off, true/false, 1/0.

How do you convert between binary and decimal?

• Binary → Decimal: add powers of 2

• Decimal → Binary: divide repeatedly by 2 and read remainders upward

What are overflow, sign magnitude, and two’s complement?

• Overflow: number too large for available bits

• Sign magnitude: one sign bit + value bits

• Two’s complement: flip bits and add 1 to make negatives

How are text, sound, and images stored digitally?

• Text → ASCII or Unicode

• Sound → sampling rate + bit depth

• Images → pixels using RGB values

Difference between lossless and lossy compression?

• Lossless keeps all original data

• Lossy removes some data to reduce size

What is Boolean logic? Main operators?

Boolean logic uses true/false values. Main operators are AND, OR, and NOT.

What are logic gates, multiplexers, and decoders?

• Logic gates perform Boolean operations using transistors

• Multiplexer selects one input from many

• Decoder activates one output pattern

What are the 4 major parts of von Neumann architecture?

• Memory

• Input/Output

• ALU (Arithmetic Logic Unit)

• Control Unit

Difference between RAM, ROM, cache, volatile, and nonvolatile memory?

• RAM: changeable temporary memory

• ROM: prerecorded memory

• Cache: very fast small memory

• Volatile: erased without power

• Nonvolatile: keeps data without power

What happens during the fetch-decode-execute cycle?

The CPU repeatedly fetches instructions from memory, decodes them, and executes them.

What do MAR, MDR, Program Counter, and Instruction Register do?

• MAR → stores memory address

• MDR → stores transferred data

• Program Counter → next instruction address

• Instruction Register → current instruction

What is parallel processing and the von Neumann bottleneck?

• Parallel processing uses multiple processors at once

• Von Neumann bottleneck happens because instructions are processed sequentially

Important networking terms?

• LAN = local network

• WAN = wide network

• Router = directs traffic

• DNS = converts names to IP addresses

• Bandwidth = connection capacity

• Wi-Fi uses IEEE 802.11

What are the 5 protocol stack layers and common protocols?

Layers: Physical, Data Link, Network, Transport, Application.

Protocols:

• HTTP → web pages

• TCP → reliable delivery

• IP → addressing/routing

Key Python number concepts?

• int = whole numbers

• float = decimals

• complex = numbers with j

• type() checks data type

• int() removes decimals

• float() adds decimals

• complex() adds +0j

• random.randrange() gives random integers after import random