A version of 3.6.12 means

• 3 is major version, increment if you have changes that break backward compatibility
• 6 is minor version, increment if you have backward compatible new features
• 12 is patch release, increment if you have backward compatible new bug fixes

• Use tilde ~1.0.4 to allow update to newer patch releases, e.g. to 1.0.5 but not 1.1.0
  • Using ~ with only major version specified will allow minor changes, e.g. ~3 updates to anything between >=3.0.0 <4.0.0 which is the same as specifying 3.x
• Use caret ^1.0.4 to allow update to newer minor releases, e.g. to 1.1.0 but not 2.0.0
  • More specifically caret allows changes that do not modify the first non-zero digit in the version, so ^0.4.2 updates to anything between >=0.4.2 <0.5.0
• Use * to allow update to newer major releases, e.g. to 2.0.0