A Pir or Peer or faqir is the name given in Punjabi / Urdu or a Muslim saint or Holy person. Pir (literally means an "old [person]") is commonly a title for a Sufi master. A 'peer' is also referred to as a Shaikh, which is Arabic for Old Man.
The title is often translated into English as "saint". In Sufism a Pir's role is to guide and instruct his disciples on the Sufi path. This is often done by general lessons (called Suhbas) and individual guidance.
Other words that refer to a Pir include, Murshid (Arabic: مرشد, meaning "guide" or "teacher"), Sheikh and Sarkar (Persian/Hindi/Urdu word meaning Master, Lord).
The path of Sufism starts when a student takes an oath of allegiance with a teacher called Bai'ath or Bay'ah (Arabic word meaning Transaction). After that, the student is called a Murid (Arabic word meaning committed one).
A Pir usually has authorizations to be a teacher for one (or more) Tariqahs (paths). A Tariqah may have more than one Pir at a time. A Pir is accorded that status by his Shaikh by way of Khilafat or Khilafah (Arabic word meaning succession). Khilafat is the process in which a Shaikh identifies one of his disciples as his successor (khalifah). A Pir can have more than one khalifah.
A Fakir or Faqir means poor generally referring to a monastic someone who gives up worldly things to live such as a saintly life in poverty.