Here is the difference between them:

Feature	any	unknown
Type safety	❌ No safety	✅ Safe
Can access properties directly?	✅ Yes	❌ No
Can call functions directly?	✅ Yes	❌ No
Need type checking before use?	❌ No	✅ Yes
Best use	When you don’t care about type checking	When type is unknown but safety is important

---

any Example

let value: any = "Raj";

value.toUpperCase(); // ✅ Works
value();             // ✅ No TypeScript error
value.xyz;           // ✅ No error

Problem with any:
TypeScript stops checking errors.

let value: any = 10;
value.toUpperCase(); // Runtime error

---

unknown Example

let value: unknown = "Raj";

value.toUpperCase(); // ❌ Error

You must check the type first:

let value: unknown = "Raj";

if (typeof value === "string") {
    console.log(value.toUpperCase()); // ✅ Safe
}

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Real-world Scenario

any

Use when:

• Migrating old JavaScript code
• Quick prototyping
• You intentionally want to skip checking

unknown

Use when:

• API response type is not known
• User input can be anything
• Safer coding is needed

Example:

function handleApi(data: unknown) {
    if (Array.isArray(data)) {
        console.log(data.length);
    }
}

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Easy Memory Trick

• any = “Do anything”
• unknown = “I don’t know yet, check first”

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Interview One-Line Answer

any disables TypeScript type checking, while unknown is a safer type that requires type checking before usage.