Secondary Memory

Duration: 4 min

This video lesson is available to enrolled students.

Return to /learn/UP-POLICE-COMPUTER-OPERATOR/computer-science/basics-of-coa/basics-of-memory/asset-secondary-memory after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About the course: About the Course
  2. General Knowledge: Polity, Physics, Biology, State Wise GK, Chemistry, History, Geography, GK- Current Affairs, Indian Economy, Static General Knowledge, Environment, Evolution of Indian Banking (Banking & Financial Awareness)
  3. Mental Aptitude and Reasoning: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Permutation and Combination, Number System, Sequence and Series (Series), Speed Time and Distance, Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Vocabulary, Profit and Loss, Arithmetic, Mental Ability, Percentage, Algebra, Mensuration and Geometry, Age Problems, Clock, Calendar, Verbal Analogy (Word Based Analogy), Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Analogy, Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Selection Decision Table (Decision Making), Cubes & Dices, Blood Relations, Venn Diagram, Logical Sequence Of Words, Inequality, Directions (Direction Test), Data Arrangement, Facts, Inference and Judgements, Syllogisms, Seating Arrangements, Ranking, Order and Sequence
  4. CS | Computer Fundamentals: Basics of COA, Number System, Number Representation, C Fundamentals, Algorithm Analysis, Input Output Organisation
  5. CS | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, SQL
  6. CS | Workplace productivity Tools: MS Office Applications, Keyboard Shortcuts
  7. CS | Computer Networks: Introduction to CN, Data Communication, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, Application Layer, Hardware Basics, Network Security
  8. CS | The Internet: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Web Publishing & Hosting, Server Side & Security, Emerging Technologies
  9. CS | Emerging Technologies: Artificial Intelligence, Emerging Tech Trends, Introduction to OS, Windows OS, Linux OS, Unix OS, JavaScript-Basics
  10. CS | Boolean algebra: Digital Systems & Boolean Basics, Boolean Expression, Boolean Minimization, Logic Gates & Hardware
  11. CS | Data Structures: Introduction to DS, Array, Stack, Queue
  12. CS | Cryptography: Society, Law & Ethics, Cyber Threats and Malware Attacks, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Electronic Data Interchange and E-Commerce, Physical Security and Cryptography Basics, Intrusion Detection Systems (IDS), Cyber Safety and Security
  13. UP Police Previous Year Papers:
  14. UP Police Full Mock Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture introduces secondary memory as non-volatile storage for permanent data retention, emphasizing the CPU Rule that requires data to be loaded into RAM before processing. It categorizes secondary storage by technology, covering magnetic media (tape and HDD), flash memory (SSDs), and optical media (CDs/DVDs). The lesson contrasts sequential access, exemplified by magnetic tape, with direct access methods like HDDs and SSDs. It concludes with industry usage examples, noting that data centers use magnetic tapes for long-term backups due to their low cost and 30+ year lifespan.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video defines secondary memory as non-volatile storage for permanent data, listing alternative names like Auxiliary or Backup Memory. It explains the 'CPU Rule' (data must load into RAM before processing) and key characteristics: huge capacity, slower speed than RAM, and non-volatility. Visual examples include HDDs, SD Cards, PenDrives, and SSDs. The lesson transitions to categorizing storage by technology, introducing magnetic media with images of a tape drive and open hard disk.

  2. 2:00 – 4:19 02:00-04:19

    The lecture details magnetic media, contrasting sequential access (magnetic tape for archiving) with direct access (HDDs for files). It introduces flash memory, highlighting SSDs as fast, reliable storage without moving parts, and optical media using lasers to read/write on plastic discs. The final section compares access methods: sequential (slowest, like a cassette tape) versus direct (fast, immediate retrieval). Industry examples show data centers using magnetic tapes for cheap, 30+ year backups.

The lecture progresses from defining secondary memory and its constraints (CPU Rule) to categorizing storage technologies. It emphasizes the trade-off between sequential access (cheap, slow, long-term) and direct access (fast, expensive, immediate). Key takeaways include the non-volatility of secondary memory and the specific use cases for each technology, such as SSDs for speed and magnetic tapes for archival backups.

Loading lesson…