This is (of course!) the writing on The Ring, in Old Elvish. The language is that of Mordor, as spoken by Gandalf at the Council of Elrond. In English it might sound a little like this:
ash nazg durbatulûk, ash nazg gimbatul,
Would you like to be able to write in Elvish? Aha, I thought so. Then here is your page, a tutorial in writing with Elvish fonts, using the Tengwar writing system developed by J.R.R.Tolkein. And no, I am not making this up.