Secondary Memory

Duration: 4 min

This video lesson is available to enrolled students.

Return to /learn/SSC-CGL-TIER-2/computer-basics-section-iii-paper-i/basics-of-coa/basics-of-memory/asset-secondary-memory after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. Paper-I | Mathematical Abilities: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Number System, Speed Time and Distance, Arithmetic, Percentage, Average, Simple Interest and Compound Interest, Profit and Loss, Partnership, Time and Work, Algebra, Mensuration and Geometry, Trigonometry, Linear Algebra
  2. Paper-I | Reasoning & General Intelligence: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Directions (Direction Test), Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Selection Decision Table (Decision Making), Logical Sequence Of Words, Crypt Arithmetic, Venn Diagram, Data Arrangement, Inequality, Analogy, Ranking, Order and Sequence, Clerical Aptitude, Verbal Classification
  3. Paper-I | English Language & Comprehension: Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Pronoun, Preposition, Articles, Direct and Indirect Speech, Conjunction, Modals, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Verbal Analogy (Word Based Analogy), Sentence Construction, Active Passive Voice (Voice), Determiner, Facts, Inference and Judgements
  4. Paper-I | General Awareness: Polity, Physics, Biology, Chemistry, Environment, GK- Current Affairs, Static General Knowledge, History, Geography, Indian Economy
  5. Paper-I | Computer Knowledge/Proficiency): Basics of COA, Transport Layer Services, Keyboard Shortcuts, MS Office Applications, MS Office by Yash Sir, Emerging Tech Trends, Society, Law & Ethics, Website, Browser & Services, Internet Fundamentals, Web Design & Development, Introduction to CN, Hardware basics, Network Security, Application Layer, Cyber and Info Security, Cyber Threats and Malware Attacks, Cyber Safety and Security, Role of Internet and Web Services, Security in Mobile and Wireless Computing
  6. Paper-II | Statistics: Statistics, Probability, Research Process Steps
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…