I keep hearing about these things, but never saw an article what Jetson is about. One of my friends said he uses the previous generation of this thing to operate security cameras?
NVIDIA has produced a "Tegra" series of System on a Chip (SoC) for a very long time. These have ARM embedded CPUs and most everything needed to implement an entire operating system, short of the power delivery and connectors. The Jetson series are the Tegra boards which first had a GPU added as well. Previously there was no embedded system with a GPU, and thus no embedded system could have done any kind of neural network real time solving.
The TK1 is their first version, the Jetson is the TK1 with a carrier board sold together as a developer system. It has the Kepler series GPU.
The TX1 is the first 64-bit Tegra, and the Jetson TX1 is a module with a developer carrier board (think of the carrier as similar to a motherboard, but carriers do not implement everything a PC motherboard would implement...much of that is within the SoC itself). This has Maxwell architecture GPU.
The TX2 is the second 64-bit version, and has the exact same module layout as the TX1, but it is much faster and uses a Pascal series GPU. The carrier board for their "development" kit is the same as the TX1, and you can call the module or module plus carrier one of the Jetson series.
Xavier is their most recent version, the layout has changed, and although being much smaller than the TX1/TX2 it is scorching fast in comparison (and TX2 was already rather fast). This uses a Volta architecture. The developer kit with a carrier is tiny. Most of the weight is in the heat sink, but there isn't much this can't do.https://elinux.org/Jetson_AGX_Xavier
Note that the 32-bit TK1 is what is known as armhf (ARMv7-a), and that 64-bit is arm64/aarch64 (ARMv8-a).