Directory Commands
Duration: 11 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- About the course: About the Course
- 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)
- 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
- CS | Computer Fundamentals: Basics of COA, Number System, Number Representation, C Fundamentals, Algorithm Analysis, Input Output Organisation
- CS | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, SQL
- CS | Workplace productivity Tools: MS Office Applications, Keyboard Shortcuts
- 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
- CS | The Internet: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Web Publishing & Hosting, Server Side & Security, Emerging Technologies
- CS | Emerging Technologies: Artificial Intelligence, Emerging Tech Trends, Introduction to OS, Windows OS, Linux OS, Unix OS, JavaScript-Basics
- CS | Boolean algebra: Digital Systems & Boolean Basics, Boolean Expression, Boolean Minimization, Logic Gates & Hardware
- CS | Data Structures: Introduction to DS, Array, Stack, Queue
- 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
- UP Police Previous Year Papers:
- UP Police Full Mock Tests:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This Linux OS lecture introduces essential directory commands through a structured table format. The instructor begins with the title slide "Linux OS Essential Commands" before presenting a three-column table titled "Directory Listing Commands." The first set of rows covers cd, mkdir, rmdir, and tree, with terminal examples showing pwd output, navigating to Documents, creating myfolder, and an rmdir error stating "Directory not empty." The table then switches to pwd, ls, ls -l, and ls -a. Handwritten red annotations progressively highlight key concepts: underlining "Full path" for pwd, explaining -l as long format with permissions like drwxr-xr-x, and identifying -a for hidden files starting with a dot such as .bashrc and .git_profile. The instructor gestures toward highlighted rows to emphasize command differences, using visual cues like red circles around hidden files and boxes around output elements. The lesson demonstrates how different ls flags change terminal output, providing concrete examples for exam revision.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a white title slide displaying "Linux OS" in large black text and "Essential Commands" below it. A bespectacled instructor in a dark blue polo appears at the lower right. The first table titled "Directory Listing Commands" emerges with columns for Command/Concept, What it Does, and Example (with Output). Initial rows cover cd, mkdir, rmdir, and tree, showing terminal panels with pwd output, cd Documents navigation, mkdir myfolder creation, and an rmdir error reading "Directory not empty."
2:00 – 5:00 02:00-05:00
The table transitions to rows for pwd, ls, ls -l, and ls -a. The instructor uses hand gestures to emphasize commands as they are highlighted on screen. Handwritten annotations break down syntax, identifying -l for long format and -a for all files including hidden ones. Example outputs display /home/user/projects for pwd, long-format listings with permissions like drwxr-xr-x for ls -l, and hidden files such as .bashrc and .git_profile for ls -a. Red underlines emphasize key terms like 'Full path' and 'details.'
5:00 – 10:00 05:00-10:00
Red teaching annotations progressively highlight command components and outputs. At 455s, underlines mark the cd description with arrows circling "cd Documents" in the example pane. At 500s, a red underline marks the mkdir label while a box highlights "myfolder" within ls output. Red checkmarks appear next to items in ls -l and ls -a outputs, and red circles draw attention to hidden files like .bashrc and .git_profile. The structured table format allows students to compare commands, their functions, and practical terminal examples side by side.
10:00 – 11:19 10:00-11:19
The final segment reinforces directory listing commands with additional red annotations. The table alternates between cd/mkdir/rmdir/tree rows and pwd/ls/ls -l/ls -a rows. Red handwritten annotations circle outputs including "myfolder," the rmdir error line, and a summary reading "3 directories, 4 files." A red box highlights hidden entries ".bashrc .git .profile" within the ls -a example. The instructor continues gesturing to explain how different flags modify terminal output, consolidating the lesson's key takeaways for directory navigation and file listing.
The lecture systematically teaches Linux directory commands using a consistent three-column table format that pairs each command with its function and terminal example. The pedagogical approach progresses from basic navigation (cd, pwd) to directory creation/deletion (mkdir, rmdir) and finally to file listing with various flags (ls, ls -l, ls -a). Visual annotations serve as the primary teaching tool, with red ink highlighting critical syntax elements like flags and output patterns. The instructor's gestures reinforce the connection between command descriptions and their practical applications. Key learning outcomes include understanding that pwd displays full paths, ls -l provides detailed permissions and metadata, and ls -a reveals hidden files starting with dots. The rmdir error example demonstrates real-world command behavior when attempting to remove non-empty directories.