Each external should include its version number as described [cnmat:node/272|here]. Packages of patches that we release with the old new Max downloads page can have their version and other information in the same format in a separate "infosource.txt" file.
Each patch or at least package should have a comment listing the version number. (E.g., the individual patches in the Spectral Tutorials don't have version numbers, but the entire tutorial package does.)
We're not consistent about the exact form of the version number, like 1.2 vs. 1.2.3. Sometimes the version number has text in it, like 1.9test. Sometimes the version number encodes the alpha/beta status, like "version 0.9alpha".
Some people use the convention that versions beginning with "0" are pre-release, and that 1.0 is the number of the first released version.
Bottom line: higher numbers are usually more recent.
