Expired60% confidenceFactExact time

Before ES6, JavaScript had only the var keyword for variable declaration.

2

Sources

60%

Confidence

Medium-term (~90 days)

Relevance

7/2/2026

First Seen

Valid until: 9/30/2026(expired)

Sources

JavaScript Fundamentals: A Complete Guide to Variables, DOM Manipulation, Event Handling, and API Calls

bilibiliFireUG技术社区6/21/2026

Related Claims

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