Software inspections are a disciplined engineering practice for detecting and correcting defects in software artifacts, and preventing their leakage into field operations. Software walkthroughs are, on the other hand, a form of software peer review in which a designer or programmer leads members of the development team and other interested parties through a software product, and the participants ask questions and make comments about possible errors, violation of development standards, and other problems.
What is the difference between the two? An inspection is a more formal process than a walkthrough, which is used to collect metrics or statistics about the software process. Walkthrough is a more informal version of an inspection.