Lesson 1.1
Primitives, Wrapper Classes & Integer Cache
Lesson 1.2.1
Arithmetic Expressions — Precedence, Type Promotion & Casting
Lesson 1.2.2
Boolean Expressions — Short-Circuit, Math API & Return Type
Lesson 1.3.1
String Immutability & Key Methods
Lesson 1.4
StringBuilder — Mutable, In-Place, Chainable
Lesson 1.5
Text Blocks — Whitespace & Escape Sequences
Lesson 1.6
Date-Time API — LocalDate, LocalTime & LocalDateTime
Lesson 1.7
Period vs Duration & The Chaining Trap
Lesson 1.8
Instant — Machine Timestamps in UTC
Lesson 1.9
Time Zones & DST — Spring Forward, Fall Back
Lesson 1.10
DateTimeFormatter — Formatting & Parsing
Lesson 1.11
Compact Number Formatting (Java 12+)