HMW is conceptually a descendent of Mech War 2 (SPI, 1979), designed by Mark Herman. But HMW is a complete redevelopment of the game system with new rules, scenarios, maps, counters, charts and tables. If you are experienced with Mech War 2 you will recognize some familiar concepts but HMW is a totally new game and you should read the rules accordingly.
HMW is a not-for-profit project that is built on the shoulders of volunteers. If you have a passion for the subject, there are many ways you can contribute.