Is there a program that can check if text in a document or pdf has been changed?

Question by PK: Is there a program that can check if text in a document or pdf has been changed?
Is there a program that can check if text in a document or pdf has been changed? Sometimes when I work as freelance artist I send out contracts for clients to sign. But one time a person tried to edit the contract before signing without telling me. Luckily I re-read what was originally sent. But a program would greatly help. Any suggestions on programs? Someone once mention a binary tracker as well? Thanks for your help.

Best answer:

Answer by Leroy Jenkins
Well, if he is writing down the signature then what I would recommend is either make it a read only program, or check its properties where it should tell you the last date it was modified… just right click and mosey through properties and you should find your solution

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