DSST 
Computer Science
College · Professional · IT · DSST Computing and Information Technology · Certificate available
326 lessons 2.6h runtime 12 units 583 links between lessons Test yourself · 12 quizzes, a mid exam, and a final
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Begin with Unit 1: What Computer Science Is. It sets the foundation for everything that follows.
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Unit 1: What Computer Science Is 23 lessons, 1 lecture part
Lecture: Watch · 22:32
- 0001 Computer Science
- 0002 "Computer Science Is Programming"
- 0003 The Algorithm
- 0004 "Algorithms Need Computers"
- 0005 Computing Before Electronics
- 0006 Halving the Haystack: Binary Search worked example
- 0007 The First Programmer
- 0008 The Four Parts of Hardware
- 0009 The Internet
- 0010 Software and the Program
- 0011 Programs Are Stored Like Data
- 0012 The General-Purpose Computer
- 0013 "Old Computers Couldn't Compute It"
- 0015 Theoretical Computer Science
- 0017 What Resists Computing
- 0019 The Digital Divide
- 0021 Data Science
- 0022 The Spreadsheet Is a Program
- 0023 When Spreadsheets End
- 0024 Machine Learning, Pointed Home
- 0031 The Y2K Lesson
- 0033 Technology Encodes Values
- 0035 One Chapter, Whole Field review
Unit 2: Computational Thinking & Design 27 lessons, 1 lecture part
Lecture: Watch · 25:24
- 0041 Computational Thinking
- 0042 "Computational Thinking Is for Programmers"
- 0043 Decomposition
- 0044 Pattern Recognition
- 0045 Abstraction
- 0046 Inductive Reasoning
- 0047 Deductive Reasoning
- 0048 The Three As
- 0049 Testing and Debugging
- 0050 Pseudocode and the Flowchart
- 0052 Parallel Execution
- 0053 "Concurrent Means Parallel"
- 0055 Recursion
- 0056 "Recursion Never Ends"
- 0057 Running a Recursion to the Floor worked example
- 0061 Adaptive Design Reuse
- 0062 The Design Component
- 0063 The Architectural Pattern
- 0064 The Heuristic
- 0065 Layering
- 0066 Componentization
- 0067 Business Solution Architecture
- 0068 The Monolith
- 0069 Microservices
- 0070 Model-View-Controller
- 0076 The Four Architecture Views
- 0085 Two Directions, One Solution review
Unit 3: Data Structures and Algorithms 49 lessons, 2 lecture parts
- 0091 The Data Type
- 0092 Algorithm and Program
- 0094 The Data Structure
- 0095 The Abstract Data Type
- 0096 "The Type Is the Structure"
- 0097 The List
- 0098 The Set
- 0099 The Map
- 0100 The Priority Queue
- 0101 The Graph
- 0103 The Array List
- 0104 The Linked List
- 0106 The Tree
- 0107 The Binary Search Tree
- 0108 The Balance Problem
- 0109 The AVL Tree
- 0110 The Binary Heap
- 0118 Algorithmic Problem-Solving
- 0120 The Problem Model
- 0121 "The Model Is the World"
- 0123 Time and Space Complexity
- 0125 Counting Steps
- 0126 Best Case and Worst Case
- 0127 The Order of Growth
- 0128 Big O Notation
- 0129 "Big O Is a Stopwatch"
- 0135 Divide and Conquer
- 0136 Brute Force
- 0137 The Combinatorial Explosion
- 0138 The Greedy Method
- 0139 "Greedy Finds the Best"
- 0140 The Reduction
- 0143 Sequential Search, Measured
- 0144 Binary Search, Measured
- 0145 Merge Sort, Run to the Floor worked example
- 0147 Quicksort
- 0148 Heapsort
- 0149 Hashing
- 0150 Depth-First Search
- 0151 Breadth-First Search
- 0152 The Minimum Spanning Tree
- 0153 The Shortest Path
- 0158 The Model of Computation
- 0159 The Turing Machine
- 0161 The Class P
- 0162 The Class NP
- 0163 "NP Means Not Polynomial"
- 0164 NP-Completeness
- 0169 From Pin to Pin review
Unit 4: Machines and Low-Level Programs 31 lessons, 1 lecture part
Lecture: Watch · 27:49
- 0171 The Computational Model
- 0172 Three Kinds of Models
- 0173 The Hardware Model
- 0174 The Programming Model
- 0175 The Abstract Model
- 0176 The Compiler and the Interpreter
- 0177 The Church-Turing Thesis
- 0179 The Level of Abstraction
- 0180 Performance or Productivity
- 0181 Machine Code
- 0182 "The Computer Runs My Code"
- 0184 Assembly Language
- 0186 Structured Programming
- 0187 Procedural Programming
- 0188 Object-Oriented Programming
- 0189 Functional Programming
- 0190 Tracing a Loop to Its Floor worked example
- 0193 The C Language
- 0194 The Pointer
- 0195 The Data Type's Budget
- 0196 The Overflow Lesson
- 0197 Compile, Link, Run
- 0201 The Core and the Multicore
- 0202 The GPU
- 0203 Parallel Programming
- 0204 Concurrent, Parallel, Distributed
- 0205 The Shared Memory Model
- 0206 The Message Passing Model
- 0209 The Embedded Computer
- 0210 Rust, Noted Once
- 0215 One Press, All the Way Down review
Unit 5: Computer Systems 29 lessons, 1 lecture part
Lecture: Watch · 27:12
- 0231 The Computer System
- 0232 Program and Data
- 0233 The Bit and the Byte
- 0234 The Executable
- 0235 The Abstraction Ladder
- 0236 The Algorithm's Three Requirements
- 0238 Bits Need a Declared Type
- 0239 "The Bits Contain the Meaning"
- 0240 Positional Notation
- 0241 The Unsigned Range
- 0242 The Sign Problem
- 0243 Two's Complement
- 0245 One String, Four Readings worked example
- 0246 ASCII
- 0247 Unicode
- 0248 The Floating Point
- 0251 The Loader and the Libraries
- 0252 The Register
- 0253 Vector Instructions
- 0256 The Memory Wall
- 0257 The Memory Hierarchy
- 0258 The Cache
- 0259 Main Memory: DRAM
- 0260 "Memory Keeps It When the Power Dies"
- 0261 Locality
- 0263 The Single-Cycle Processor
- 0264 Pipelining
- 0265 Moore's Law and Dennard Scaling
- 0270 One Song, Every Layer review
Unit 6: Operating Systems 26 lessons, 1 lecture part
Lecture: Watch · 26:05
- 0291 The Operating System
- 0292 The Mediator
- 0293 "My App Talks to the Hardware"
- 0294 Isolation
- 0296 Primary and Secondary Memory
- 0297 Kernel Mode and the System Call
- 0298 The OS Components
- 0301 The Process
- 0302 The Process Control Block
- 0303 The Thread
- 0304 Multitasking and the Time Slice
- 0305 Scheduling
- 0306 The Three Process States
- 0307 The Race Condition
- 0308 The Semaphore
- 0309 Round-Robin, Run to the Clock worked example
- 0313 Virtual Memory
- 0314 The Translation Lookaside Buffer
- 0316 The File
- 0317 The File System
- 0318 The Directory
- 0319 Reliability
- 0321 The Protection Triad
- 0322 Authentication
- 0323 Two-Factor Authentication
- 0327 The Referee Revealed review
Unit 7: High-Level Programming Languages 32 lessons, 1 lecture part
Lecture: Watch · 29:46
- 0351 The High-Level Language
- 0352 Cross-Platform Compatibility
- 0353 Judging a Language
- 0354 Fortran, the First Compiler
- 0355 COBOL, the Business Tongue
- 0356 BASIC to Visual Basic
- 0357 Pascal and C, the Block Builders
- 0359 The Primitive Type
- 0360 The Composite Type
- 0361 One String, Two Standings
- 0362 The Variable as Name-Value Pair
- 0363 The Reference Variable
- 0364 Strong Typing
- 0365 Coercion and the Type Cast
- 0366 "The Cast Is Free"
- 0367 The Expression
- 0368 Flow of Control
- 0369 The Scope
- 0370 Runtime Error or Exception
- 0371 The Cast That Dropped Four Bytes worked example
- 0373 Encapsulation
- 0374 Inheritance
- 0375 Polymorphism
- 0376 Degrees of Object-Orientation
- 0377 Concurrency in the Language
- 0378 The Critical Section
- 0379 The Scripting Language
- 0381 Compiler and Interpreter, Contrasted
- 0382 The Three-Stage Compiler
- 0383 Bytecode and the Virtual Machine
- 0384 Just-in-Time Compilation
- 0389 Choosing the Language, Receipts Attached review
Unit 8: Data Management 29 lessons, 1 lecture part
Lecture: Watch · 27:41
- 0411 Data, Information, Database
- 0412 Data Management
- 0413 The Database Management System
- 0414 The Data Model
- 0415 The Data Dictionary
- 0416 Data Quality's Three Tests
- 0417 The Four Sublanguages
- 0420 The Relational Model
- 0421 Keys: Super, Candidate, Primary
- 0422 The Foreign Key
- 0423 SQL
- 0424 The Transaction
- 0425 ACID
- 0426 "ACID Costs Nothing"
- 0427 Normalization
- 0428 Denormalization
- 0431 The Nonrelational Database
- 0432 The Key-Value Store
- 0433 The Document Store
- 0434 The Graph Database
- 0437 The Data Warehouse
- 0438 Extraction, Transformation, Loading
- 0439 The Data Mart
- 0440 The Virtual Data Mart
- 0441 The Data Lake
- 0442 Big Data
- 0443 Learning Tools, Pointed Elsewhere
- 0445 Splitting the Table worked example
- 0449 One Purchase, Fully Accounted review
Unit 9: Software Engineering & Architecture 26 lessons, 1 lecture part
Lecture: Watch · 26:17
- 0471 Software Engineering
- 0472 The Four Ps
- 0473 The Team's Roles
- 0474 The Generic Framework
- 0475 The Prescriptive Family
- 0476 The Waterfall
- 0478 Agility
- 0479 Scrum's Cast
- 0480 The Sprint
- 0481 Review and Retrospective
- 0484 Refactoring
- 0485 "Refactoring Rewrites Behavior"
- 0486 Continuous Integration
- 0487 DevOps
- 0488 Testing's Purpose
- 0489 The Testing Ladder
- 0490 Acceptance and Friends
- 0491 The Regression Suite
- 0492 Free and Open-Source Software
- 0493 "Free Means Gratis"
- 0495 The Pattern
- 0496 The Pattern Hierarchy
- 0497 The Enterprise Architecture Framework
- 0498 The Blueprint
- 0500 One Story, One Sprint worked example
- 0505 The Build, End to End review
Unit 10: Web & Cloud 24 lessons, 1 lecture part
Lecture: Watch · 24:09
- 0541 The Web's Founding Move
- 0542 Request and Response
- 0543 HTTPS
- 0544 Web 1.0, Then 2.0
- 0545 AJAX
- 0546 The Single-Page Application
- 0547 Web 3.0 and the Distributed Ledger
- 0549 Native, Web, Hybrid
- 0552 The Cloud
- 0553 Cloud-Native's Four Principles
- 0554 The Container
- 0555 Container Orchestration
- 0556 Cloud-Based or Cloud-Native
- 0559 The Three Service Models
- 0560 Infrastructure as a Service
- 0561 Platform as a Service
- 0562 Software as a Service
- 0563 Bare Metal to Serverless
- 0564 The Four Deployment Models
- 0565 The Hybrid Cloud
- 0566 The Multicloud
- 0568 Intelligence, Pointed Home
- 0570 One Tap, Round Trip worked example
- 0575 The App Ascends review
Unit 11: Security & Governance 24 lessons, 1 lecture part
Lecture: Watch · 24:39
- 0611 The Cyber Resource
- 0612 The Six Qualities
- 0613 The Security Policy's Assets
- 0614 Personally Identifiable Information
- 0615 Nonrepudiation
- 0618 Malware
- 0619 Virus and Worm
- 0620 "Every Infection Is a Virus"
- 0621 Rootkit and Backdoor
- 0622 The Trojan Horse
- 0623 The Botnet
- 0624 Ransomware
- 0625 The Insider Threat
- 0626 Phishing
- 0627 The Distributed Denial of Service
- 0628 The Advanced Persistent Threat
- 0629 How Malware Gets In
- 0632 Cryptography's Cast
- 0633 The Substitution Cipher
- 0634 The Transposition Cipher
- 0635 Public and Private Keys
- 0636 Responsible Computing
- 0640 One Word, Enciphered worked example
- 0645 The App Under Attack review
Unit 12: Course Capstones 6 lessons, 1 lecture part
Who this subject is for
- Students preparing for the DSST Computing and Information Technology exam
- IT support and operations staff
- Students heading into computing
- Analysts and new developers
- Anyone who wants to understand how computers and networks work
Why Computer Science matters
Computing and information technology sit underneath almost every modern job. It is the foundation for:
- Programming
- Networking
- Cybersecurity
- Data and databases
- Artificial intelligence
Time to complete
- of lessons (326, measured)
- 2.6 h
- of lectures (13)
- 5.5 h
- learning hours on the certificate, with quizzes and the final
- 12.5 h
Times are measured from the recordings and the exam time limits. Go at your own pace; nothing expires.
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