JMS allows your users to use the same login id & password for *all* your sites. JMS also allows you to execute custom database queries upon user events, such as login, logout, updating profile, creation, etc.

JMS also allows you to synchronize your content across multiple domains the same way you can synchronize your users.

JMS Can same other component?

thanks a lot and sorry my bad english

As explained in product detail and FAQ,
JMS does NOT share the content between the websites.
This means that there is no synchronisation in any maner.
The users are not shared.
See FAQ /faq#sec-73
/faq#sec-12
/faq#sec-72

Only the component "Articles Sharing for JMS" can display articles, categories, sections from any websites defined in JMS.

I also suggest you that you have a look in the video present in the tutorial step 0 that present you the concept of Joomla Multi Sites
www.jms2win.com/tutorial