"Not spam" refers to legitimate messages or content that are relevant and useful to the recipient. These can include important emails from friends, family, or businesses that you have opted to receive updates from. Unlike spam, which is often unsolicited and irrelevant, "not spam" communications provide value and foster meaningful connections. In the digital world, "not spam" can also apply to social media posts, newsletters, or notifications from apps like Facebook or Twitter. These messages are typically tailored to your interests and preferences, ensuring that you stay informed and engaged without being overwhelmed by unwanted content.