Quick meaning
A security flaw in software that is unknown to the developer and has no fix yet, making it especially dangerous.
Think of it like this
Like a hidden crack in a bank vault's wall that no one knows about yet.
Where you may see this
You may see this in login screens, warning messages, banking apps, or scam-prevention advice.
Why it matters
Understanding this word helps you protect your money, personal information, and online accounts.
Say it simply
Zero-Day Vulnerability means: A security flaw in software that is unknown to the developer and has no fix yet, making it especially dangerous.