What postcard is this - old vintage Nepal card or postcard ?

Well, it's actually not a postcard -- although it looks quite the same and the purpose, too, is almost same. It's an aerogram. If you don't know what that is, here is it's dictionary definition: a sheet of lightweight paper, bearing an official postal stamp imprint, that is folded to form its own envelope and can be sent via airmail at a special, low rate because of its standard size, light weight, and lack of enclosures. Such enveloped used to be used in the past to minimise cost and make writing easy -- in India and Nepal at least. I don't know about western countries. With the advent of more advanced communication techologies there use has stopped these days. The content of the postcard is as Walkers and Koranga have written, however, there is no mention that it was from Prithvi Bir Bikram Shah Dev's time.. It's a wise guess.. The date could be anything before the time of King Mahendra.. Because that is when, they started calling His Majesty's Government from Nepal Government.

Its post card The first line (left) says Nepal Sarkar which means Nepali Government. The first line (right) says Hulak Patra which means Post card The second line says "Yeta tira pathaune ra pauneko naam ra pata matra lekhiyos" which means In here just write the name of sender and reciver and address name please. Date probably about 1970s Its not a commemoraive card. Its a normal back of post card.

I agree with Walkers, but the dateDanitld be around Prithvi Bir Bikram Shah Dev's time (Vikram Sambat)