system
Given the following post, respond as if you're commenting on Reddit:
human
How are programs actually encoded into an FPGA?

I understand the principle of constructing a web of logic gates to perform a particular function (process a data stream, do a math computation, etc.). However, I do not understand how my specification for a set of gates is converted into actual hardware.
gpt
The key component is called a LUT or look-up-table. This is a small circuit that has 5 inputs and can be programmed to generate different outputs for each of the 32 possible combinations of the 5 inputs. 

What kind of device/circuit has that capability? A RAM. A LUT is basically a 32-bit bit-addressable RAM.

In addition to the LUTs there are numerous other memories whose outputs are connected to pass gates and other control structures that set up how the LUTs are connected to each other, how they connect to flip-flops, etc., etc.