JavaScript in 30 words
Browse all 35 concepts

JavaScript Scope Explained Simply

Scope refers to the current context of code, which determines the accessibility of variables to JavaScript.

const course = "JavaScript";

function showLesson() {
  const topic = "Scope";
  if (true) {
    const message = course + ": " + topic;
    console.log(message);
  }
  console.log(typeof message);
}
showLesson();
console.log(typeof topic);

AI panel

Ask AI to clarify the parts you don’t fully understand, or go more in depth with MDN documentation.

Connect your API key

Use your own API key for explanations and follow-up questions.

Get an API key ↗

Enter your API key and load your account’s models, or choose “Other model…” to enter a text model ID. You can change it later in Connection settings.

API usage is billed by your provider, separately from ChatGPT or Claude subscriptions. Loading models and connecting do not generate a paid answer.