Who named God as ‘Narayana’ and what does the name signify?

We are all given a name by our parents or well-wishers at the time of the birth. What about God? How did he get all the names that we all refer him by? An excerpt of Swamiji’s discourse on this topic during Sri Sita Rama Kalyanam at Toronto, Canada just for our dear readers!
Source: Varija News