Shaytan is referring to The Devil, also known as Iblis. Satan is appointed to misguide people until the day of Judgement.
In Islam, the Devil is known as ʾIblīs (Arabic: إبليس, plural: ابالسة ʾAbālisa) or Shayṭān (Arabic: شيطان, plural: شياطين Shayāṭīn). According to the Quran, God created Iblis out of "smokeless fire or from the pure flame of fire" (along with all of the other jinn) and created man out of clay. The primary characteristic of the Devil, besides hubris, is that he has no power other than the power to cast evil suggestions into the heart of men, women, and jinn, although the Quran does mention appointing jinn to assist those who are far from God in a general context. "We made the Shayatin (devils) ʾAwliyāʾ (protectors and helpers) for those who believe not." (سورة الأعراف al-ʾAʿraf, Chapter #7, Verse #27)