Spam - is unwanted, usually mass messages sent via email or other means of communication (SMS, messengers, etc.). The word "spam" became known specifically in this context and is very different from its original meaning, and its history is quite interesting.
Spam. The Beginning.
Initially, "SPAM" was a trademark of a canned meat product produced by Hormel Foods Corporation in the USA back in 1937. The name "Spam" is a portmanteau formed from the words "spiced ham," as the product consisted of pork with added spices.
Spam Becomes a Meme.
In the 1970s, SPAM gained popularity in the British comedy television show "Monty Python's Flying Circus." In one episode, a café offered many dishes with "Spam," and the word "spam" was repeated many times, disrupting normal communication.
Monty Python - SPAM
Spam and the Internet.
At the beginning of the existence of the internet and online chats, when toxic users disliked conversations in chats or forums, they massively copied and pasted text from the "Monty Python" episode, flooding discussions with unnecessary content, just as the café menu was flooded with "Spam" in the episode.
This analogy became popular for describing electronic messages that are sent en masse and often unwanted, just like the overflowing menu in the TV show.
Thus, "spam" transformed from a product name into a well-known term for describing mass mailing of electronic messages.