What are the -Xms and -Xmx parameters when starting JVM?

Question

Please explain the use of Xms and Xmx parameters in JVMs. What are the default values for them?

Answer 1

-Xms initial heap size for the startup, however, during the working process the heap size can be less than -Xms due to users' inactivity or GC iterations. This is not a minimal required heap size.

-Xmx maximal heap size