Can you explain what a domain-specific language (DSL) is and what makes it special?

The Domain-Specific Language (DSL) is a specialized programming language or a set of constructs created to solve problems within a specific domain. Unlike general-purpose programming languages, DSLs focus on convenience and expressiveness within their area.

Features of DSL:

• Simplification and improved readability of code through the use of terms and constructs close to the domain.
• Limited scope of application, allowing focus on specific tasks.
• Can be embedded (internal DSL) — implemented within a general programming language, or external (external DSL) — a separate language with its own syntax.

An example of an embedded DSL in Kotlin is creating UI with functions and lambdas, which read almost like a declarative language:

fun html() {
    body {
        h1 { +"Title" }
        p { +"Paragraph text" }
    }
}

This approach simplifies development and maintenance of code aimed at a specific task.