Bacteria, ubiquitous in their presence, engage in intricate molecular communication with neighboring prokaryotic and eukaryotic cells to thrive within their respective niches. This communication involves a diverse array of sophisticated machinery developed by bacteria to carry out various activities. Our focus lies on elucidating the mechanisms of novel contact-dependent communication facilitated by bacterial nanotubes. These nanotubes act as conduits for the exchange of cytoplasmic molecules—including amino acids, toxins, antibiotic markers, and plasmids—among bacteria of different species, as well as between bacteria and their human host cells. This exchange fosters intra- and inter-kingdom crosstalk, shedding light on the complex interactions shaping microbial communities and their hosts.