What is the real concept of Brahmacharya as per Vedas or Scriptures?

What is the real concept of brahmacharya as per vedas or Hindu scriptures ?

  • Is it about remaining bachelor or about celibate?
  • Or is it abstaining from inter course?
  • Or controlling desires?

Vedas authority would be more desirous.

One of the reference I found this- but unable to understand this completely.

Now what people call yajña(sacrifice) is really Brahmacharya, for only by means of Brahmacharya does the knower attain that world (of Brahman). And what people call Ishta (worship) is really Brahmacharya, for only worshipping by means of Brahmacarya does one attain the Atman (the liberated Self). Now, what people call the Sattrayana (sacrificial session) is really Brahmacharya, for only by means of Brahmacharya does one obtain one’s salvation from Sat (Being). And what people call the Mauna (vow of silence) is really Brahmacharya for only through Brahmacharya does one understand the Atman and then meditate. Now, what people call a Anasakayana (vow of fasting) is really Brahmacharya, for this Atman never perishes which one attains by means of Brahmacharya. And what people call the Aranyayana (life of a hermit) is really Brahmacharya, for the world of Brahman belongs to those who by means of Brahmacharya attain the seas Ara and Nya in the world of Brahman. For them there is freedom in all the worlds.

— Chandogya Upanishad, VIII.5.1 – VIII.5.4

Source: stackexchange.com