Here's why:
* Speech is a form of communication using words and language. Laughter is a vocalization, but it doesn't convey specific messages or ideas in the same way language does.
* Speech is structured and organized. Laughter is more spontaneous and often involuntary, lacking the grammatical rules and syntax of language.
* Speech is intentional. While laughter can be intentional in some cases (e.g., forced laughter), it's primarily an automatic, emotional response.
However, laughter can be considered part of communication. It conveys emotions and can be used to build relationships, express agreement, or even signal discomfort.
In conclusion, laughter and speech are distinct forms of communication, each serving different functions.