Instructor: First off, let's look at the primary components and the ones you'll use or reference the most.
Reset button. Works as named. Briefly turn off your board and turn it back on.
Setup button. Primarily you use setup to put your board into listening mode, which is how you pass WiFi credentials to your board.
RGB LED. This is the board status LED. This LED gives you all of the information you'll need at a glance to know how your board is doing.
On-board LED. The On-board LED is tied to the D7 pin. For the classic blink example, you start with this LED as there is no setup required to affect it.
The pins. The Particle Photon has six analog pins, eight digital pins of voltage-in, voltage-out, two ground pins, two serial pins, a DAC, a wake up, a reset, and a battery pin. The analog and digital pins can also run double-duty in various capacities.
That's it. Now you're ready to get started with your Particle Photon.