A little more C#.
A little more confidence.

1. 01

   Run and read a C# program

   Beginner

   Follow a small program, recognize statements, and print named values.

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   Open chapter: Run and read a C# program
2. 02

   Values, types, and strings

   Beginner

   Predict expression results before choosing a variable type.

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   Open chapter: Values, types, and strings
3. 03

   Create and read an array

   Beginner

   Store several values of one element type and inspect their positions.

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   Open chapter: Create and read an array
4. 04

   Decisions, loops, and methods

   Beginner

   Turn requirements into conditions and reusable computations.

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   Open chapter: Decisions, loops, and methods
5. 05

   Arrays, value copies, and shared references

   Intermediate

   Determine exactly which assignments create an independent value.

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   Open chapter: Arrays, value copies, and shared references
6. 06

   Pattern matching and exhaustive decisions

   Intermediate

   Use patterns to connect input shape with permitted operations.

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   Open chapter: Pattern matching and exhaustive decisions
7. 07

   Classes, properties, and invariants

   Intermediate

   Model state with controlled updates and clear object identity.

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   Open chapter: Classes, properties, and invariants
8. 08

   Collections and LINQ pipelines

   Intermediate

   Select, transform, and materialize sequences deliberately.

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   Open chapter: Collections and LINQ pipelines
9. 09

   Dictionary contracts and equality rules

   Intermediate

   Keep missing keys distinct from stored default values.

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   Open chapter: Dictionary contracts and equality rules
10. 10

    Delegates and captured state

    Intermediate

    Pass behavior while making its dependencies visible.

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    Open chapter: Delegates and captured state
11. 11

    Iterator methods and deferred execution

    Advanced

    Know when a sequence actually performs its work.

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    Open chapter: Iterator methods and deferred execution
12. 12

    Interfaces and virtual behavior

    Advanced

    Separate a required capability from its implementation.

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    Open chapter: Interfaces and virtual behavior
13. 13

    Nullable values and explicit failures

    Intermediate

    Separate absent data, valid defaults, and exceptional failures.

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    Open chapter: Nullable values and explicit failures
14. 14

    Deterministic cleanup with using

    Advanced

    Tie resource lifetime to the scope that owns it.

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    Open chapter: Deterministic cleanup with using
15. 15

    Tasks, asynchronous completion, and failure

    Advanced

    Return completion handles that callers can actually await.

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    Open chapter: Tasks, asynchronous completion, and failure

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