If the parties put their fingerprints on the contract, it will be considered as valid as the signature in law. The biggest advantage of handprint is that it is not as easy to alter as signature. Sometimes there are many words when signing, which gives the parties a chance to cheat.
With regard to handprints, modern society generally does not use them alone, unless the parties can't write, and the advantage of handprints is to clarify their identities. The most prudent method is to combine the signature with the thumb print.
Signing, stamping and fingerprinting are related to everyone's vital interests. Be careful before writing. If there is compulsion, keep the evidence. At the same time, it is necessary to read the contents of the contract agreement clearly, and never sign, seal or press the handprint casually because of emotion.