← PHP theorytheory 0/50 · 0%

level 1

Curious · 0 XP

streak

perfect

badges

100 XP to Apprentice

Fundamentals · easy

2. Variables & Constants

Storing and naming values.

1 min read2 questionsup to 50 XPtopic 2/50

Read in another language

AI translates the explanation and quiz text while preserving code and answer scoring.

Variables in PHP start with a dollar sign, e.g. $name, and are case-sensitive. They do not need explicit type declarations because PHP is dynamically typed.

Constants are defined with define() or the const keyword and cannot be changed once set, making them useful for configuration values.

How to study this topic

1. Read the explanation once end to end, skipping the code.
2. Re-read the code snippets and say out loud what each line does.
3. Answer the quiz without scrolling back — that is the real check.
4. Read every explanation, even for the answers you got right.

Scoring

· Up to 30 XP from quiz accuracy.
· +15 XP for a perfect first attempt.
· +5 XP while a 3-day streak is running.
· 75% or higher marks the topic complete.

Badges

First light

Pass your first topic

Sharp shooter

3 perfect first-try quizzes

On a roll

Study 3 days in a row

Week warrior

Study 7 days in a row

Grinder

Earn 500 XP

Deep diver

Earn 1500 XP