A more thorough explanation:

Waiver of immunity is the act of giving up the right against self-incrimination and proceeding to testify. Immunity means exemption from a duty, liability, or service of process. There are different types of immunity:

• Absolute immunity: A complete exemption from civil liability, usually afforded to officials while performing particularly important functions, such as a representative enacting legislation and a judge presiding over a lawsuit.
• Qualified immunity: Immunity from civil liability for a public official who is performing a discretionary function, as long as the conduct does not violate clearly established constitutional or statutory rights.
• Transactional immunity: Immunity from prosecution for any event or transaction described in the compelled testimony. This is the broadest form of immunity.

For example, a police officer who is sued for using excessive force may claim qualified immunity if they were performing their duties in good faith and did not violate any clearly established constitutional or statutory rights. This means that they cannot be held liable for damages in a civil lawsuit.

Another example is when a witness is granted transactional immunity in exchange for their testimony in a criminal case. This means that they cannot be prosecuted for any event or transaction described in their testimony.