meta name="generator" content="7.3.5.244" appears in the head of an adobe muse based static site. What does the "7.3.5.244" mean/do?
In this case, is a version number. Specifically, it is the version of Muse used to generate the site. Version 7.3 is the current version.
More generally, the HTML specification allows the content attribute of a <meta> tag to contain anything describing the generator. A version number is common, but the name of the product is often included for clarity. For example:
<meta name="generator" content="WordPress 2.5.1" />