Habeas Corpus; Peremptory Writ; Preliminary Citation; Order to Produce Body

What is the difference between peremptory writ from preliminary citation?

[1] Peremptory writ of habeas corpus unconditionally commanding the respondent to have the body of the detained person before the court at a time and place therein specified.
[2] Preliminary citation requiring the respondent to appear and show cause why the peremptory writ should not be granted.
[3] An order to produce body is not exactly a grant of the remedy of habeas corpus
In a habeas corpus petition, the order to present an individual before the court is a preliminary step in the hearing of the petition. The respondent must produce the person and explain the cause of his detention. However, this order is not a ruling on the propriety of the remedy or on the substantive matters covered by the remedy. Thus, the Court's order to the Court of Appeals to conduct a factual hearing was not an affirmation of the propriety of the remedy of habeas corpus. (In the Matter of the Petition for Habeas Corpus of Alejano vs. Cabuay, G.R. No. 160792, August 25, 2005