Who follows which yana (Vajrayana, Hinayana or Mahayana)? I have heard about these traditions: Vajrayana, Mahayana, and Hinayana. In today's world, Buddhist people dwell in South Asia and East Asia. Who among them follows each particular sect? Does anybody follow more than one of them?
In today's world Buddhist people dwell in South Asia and East Asia . Who among themselves follows particular sect.

Wikipedia's Schools of Buddhism article has a map.

Does anybody follows more than one of them?

I'm not sure that it makes sense to talk of "following a sect". If you think of them as "schools" then, yes, I'm pretty sure that there are some (or many?) people who learn from more than one school.

For example the Pali canon could be associated with the Theravada school, but it is studied by people who also learn from other (e.g. Tibetan or Zen) teachers.

I can't tell you how wide-spread that practice is geographically, but there are certainly some users like that on this site.

And people sometimes emphasize what the "sects" of Buddhism have on common (What teachings do all schools of Buddhism share?, and One Vehicle for Peace which is referenced from that topic).



Incidentally, please refer to this topic: How should we police the use of the word Hinayana?

Also, One Vehicle for Peace (referenced above) says,


  It is universally accepted by scholars that the terms Hinayana and Mahayana are later inventions by Mahayanists. Theravada cannot be included in either of these divisions. Historically speaking Theravada already existed long before these two terms came into being. etc.


The Wikipedia map I referenced shows Theravada, Mahayana, and Vajrayana (not Hinayana, Mahayana, and Vajrayana) as you wrote in the question.

Dhammadhatu's answer is about Hinayana ("individual enlightenment vehicle") since that's what you asked about -- it's one of the yanas which are described in Mahayana doctrine. But maybe (since you asked about different schools in different geographical places) you intended to ask instead about Theravada (which I think of as "old school" or "original school" or literally "school of the elder monks").