Talk:Hangeul step 3/fr

I don't understand the following part: "Do note that this is not exactly the /r/ sound from English, but instead is a flap R sound like the D sound in the word 'rider' or double T sound in the word 'better'. If you are familiar with the sounds of Spanish it is very similar to the R sound in the word 'caro.' For full information about this letter, see ㄹ. "

Why talking about D and T for the R sound ? o_O I'm lost