What are optionals in Swift and why are they important?

Optionals are a fundamental Swift feature that represents values that might be absent (nil).\n\n• **Purpose:**\n• Handle absence of values safely\n• Prevent null pointer exceptions\n• Make code more explicit about potential nil values\n• Compile-time safety for nil handling\n\n• **Declaration:**\n\nvar optionalString: String? = "Hello"\nvar optionalInt: Int? = nil\n\n\n• **Unwrapping Methods:**\n\n// Force unwrapping (use carefully)\nlet value = optionalString!\n\n// Optional binding\ let unwrapped = optionalString {\n print(unwrapped)\n}\n\n// Nil coalescing\nlet result = optionalString ?? "Default"\n