So where did it originate from?
Though there are a number of theories about the origin of Urdu (that is, aside from camp language theory) that say, for example, Urdu has its origin in Punjabi, or it was born in Deccan or in Sindh, few have stood up to research based on historical linguistics and comparative linguistic. Of the theories considered to be holding water, the most plausible seems to be the one that says Urdu developed from some dialects spoken in and around Delhi in the 11th and 12th centuries AD. These dialects include Brij Bhasha, Mewati, Khari Boli and Haryani, which, in turn had developed from Apbhransh. The name Apbhransh refers to a number of languages/dialects which were born from Prakrit languages. The question that still requires a precise answer is: from which Apbhransh did Urdu originate? Some linguists believe it was most probably an offshoot of Shourseni Prakrit, spoken in and around Mathura. Dr Gian Chand Jain says it was Khari Boli.
In brief, Urdu is much older than just a few hundred years and its roots go right back to Sanskrit. At least, it has been established beyond doubt that Urdu is not a camp language.
I doubt that Urdu was the language of the Mughal Army camp as is claimed, given that uptill the 19th century Farsi/Persian used to be the official language and not Hindustani/Urdu.
Also, it's origins are from Hindustani of the Cow Belt mixed with Farsi and Arabic not from Punjabi.
Punjabi is a North-Western Indo-Aryan language, along with Sindhi and Kashmiri-Pahari, as compared with Hindustani/Urdu which is a Central Indic language.
These regional zones are prominent as they can differentiate languages a lot e.g Persian/Farsi is a South-Western Iranic language and Pashto is an Eastern Iranic language yet they average Farsi speaker cant understand Pashto or vice versa apart from borrowed words.
(from Britannica)
"Particular sound changes also characterize languages of the northwest. In this group, an older voiceless stop (
e.g., t) became voiced (
e.g., became
d) after a nasal sound; in other areas, the voiceless stop is retained: Kashmiri
dand, Punjabi
dənd, Sindhi
ḍəndu “tooth” (the
ḍ in Sindhi is an imploded stop; see below) but Assamese, Bengali, Hindi, Gujarati, Marathi
dãt, Sinhalese
dətə (Sanskrit
danta-). Moreover, in the northwest group a voiced stop (
e.g., d) preceded by a nasal was assimilated to the latter, resulting in two nasals, which were subsequently reduced to one in some areas; in the rest of New Indo-Aryan, the vowel preceding the nasal was nasalized. Thus, Kashmiri
don “churning stick,” Sindhi
ḍənu “tribute,” Punjabi
dənn “fine,” Lahnda
ḍənn “force,” Kumauni
dan “roof” contrast with Assamese
dãr “pole,” Bengali
dãṛ “oar,” Hindi
dãḍ “oppression, fine,” and others; all forms derive from Old Indo-Aryan
daṇḍa- “stick, staff, club, royal power, fine, punishment.”
The North-Western Indo-Aryan languages retain many of the original characteristics of the Old Indo-Aryan languages of the Rig Vedic period as compared to other groups like Central Indic. They also have affinity with Dardic languages which are the best preserved descendant languages of original Rig-Vedic Sanskrit.
Punjabi itself is unique in this respect as it's the only Indo-European language that is fully tonal.
"Punjabi is distinguished from other members of the northwest group by its tonal system, having low (ˋ), mid (¯), and high (´) tones."
Personally, I think English should have been the official language of Pakistan along with the native languages (Punjabi, Pashto, Sindhi, Balochi etc.) and native languages kept at provincial level. Making Urdu the national language and discouraging the native languages is making Pakistan into a cultural colony of 'Gangadesh'.