which sql server edition is good for practice Which SQL Server (free/trail) would be good to install, which requires minimum resource and have maximum features. I mean, I can practice mirroring,logshipping and replication. I found this link, but confuse with enterprise and standard edition.
The 180 day evaluation version from Microsoft is Enterprise Edition.  AFAIK there is no ability to "trial" Standard edition from Microsoft outside of a licensing agreement you might have.

From the point of view of overhead between editions, there's negligible difference.  

If you want something longer than 180 days, get the developer edition as its feature complete compared to Enterprise but only $50 from Amazon