Define Fall Off The Grid Meaning

Fall Off The Grid
To (seemingly) disappear from the face of the earth
Disappear to a place one would be very unlikely to be found.

What happened to Tom? I haven't talked to him since ten years ago.

Last time I heard, he got caught up in a drug-related arrest. Somehow escaped from prison and was forced to fall off the grid, probably somewhere in the Amazon Rainforest living with them Natives by now.
By Anette