What may have pili?

Pili are hair-like structures found on the surface of many bacteria. They are primarily composed of protein and play crucial roles in attachment to surfaces, aiding in colonization and biofilm formation. Some pili, known as fimbriae, help bacteria adhere to host tissues, while others, called sex pili, are involved in the transfer of genetic material between bacterial cells during conjugation. Additionally, pili can contribute to motility and immune evasion.