Apa sih Utaite itu?
is a Japanese term for people who cover previously released songs and post them on Nico Nico Douga and YouTube under the utattemita category. The term "utaite" is unique to Nico Nico Douga singers, making it different from "kashu" (歌手 kashu), which means "singer" in general.

Generally, utaite do cover songs for VOCALOID original songs, anime and game related songs, and J-Pop. They also do parodies with different lyrics for popular songs, intended for amusement.

Most utaite exclusively cover songs and upload under the utattemita section, but some of them have doujin circles and release original music/drama CDs during events like Comic Market and VOCALOID M@ster, frequently referred to as Comiket and VoMas respectively. A few utaite also have become partly or wholly professional singers and have released/will release their albums under official labels. Some examples are Valshe, Piko, clear and 96Neko.

Kalo producer?
is a term that describes anyone who creates their own original songs. Some are using the VOCALOID software. Those are usually identified in the community by the honorific "P" after their nickname (e.g. RyuuseiP). However some also create original songs. On Nico Nico Douga they're commonly referred to as Nico Nico Indies (NNI).

In rare cases, producers can also create PV's or artwork for their own works.

Producers who are also utaite, such as Tourai and DECO*27, are sometimes tagged with Utau P series.

The following is a list of utaite who are also producers. Some also do self-covers of their own produced works.

Anime related gak sih?
Oh ya jelas, karena sekarang gak sedikit para producer & utaite yang ngecover lagu-lagu anime, bahkan mengcompose lagu untuk Opening & Ending anime yang udah tayang.