String interpolation is the ability to embed variable or expression values directly within a string literal. It offers better readability than string concatenation and is widely adopted in modern programming languages.

JavaScript uses template literals (`Hello, ${name}!`) for string interpolation. Enclosed in backticks, any expression can be placed inside ${}. JavaScript ES6 guides cover template literal usage in detail.

Python uses f-strings (f"Hello, {name}!"), Ruby uses "Hello, #{name}!", and C# uses $"Hello, {name}!". The syntax varies by language, but the concept is the same.

String interpolation requires security awareness. Interpolating user input directly can lead to SQL injection or XSS vulnerabilities, making proper escaping essential. Security programming guides teach safe string handling practices.