What primitive data types exist in Kotlin and what are available in Java?

In Kotlin:

• Byte (8 bits)
• Short (16 bits)
• Int (32 bits)
• Long (64 bits)
• Float (32 bits)
• Double (64 bits)
• Boolean (logical value)
• Char (character)

In Java:

• byte (8 bits)
• short (16 bits)
• int (32 bits)
• long (64 bits)
• float (32 bits)
• double (64 bits)
• boolean (logical value)
• char (character)

In Kotlin, primitive data types are represented as objects, and the compiler performs "unboxing" for performance optimization when necessary. In Java, primitive data types are not objects, although there are corresponding wrapper classes (e.g., Integer).