The standard library

The standard library, sdp, has the nodes you need to start. Studio shows them in its library panel with their pins and descriptions.

Library	Nodes
sdp/core	add, subtract, multiply, divide, equal, greater, less, and, or, not, if-else, sample, defer, boot, continuously, constants and conversions between types
sdp/logic	and, or, xor, not, any, gate, flip-flop, pulse-on-change, pulse-on-true
sdp/math	abs, clamp, count, map-range, max, min, round
sdp/time	clock, delay, debounce, system-time
sdp/gpio	digital-read, digital-write, analog-read, pwm-write
sdp/text	format-number, join, length
sdp/debug	watch (see a value live while the program runs), tweak-boolean, tweak-number, tweak-string-16 (change a value live without rebuilding)

The debug nodes only do something in debug builds, when the board is connected to Studio. In a release build they're left out.