When coming from another language it is good to find out where D stands in relation to it. There is the feature list which states if a feature exists or not and possibly an explanation. For a side-by-side comparison of many languages: Languages vs D or you can look at code snippets of from Rosetta Code.
A very superficial way to find out the popularity of D in relation to other languages can is at the Tiobe Index website.
For information about syntactical differences or gotchas when coming from another language choose your language below.
If you are interested in converting your code to D start by looking at the Porting Overview.