Could you please tell me what spider this is? Also it's behavior and toxicity?
Your spider is in a family of spiders known as the orb weaver spiders (family Araneidae). I cannot identify this spider from the digital images, but suspect that it is in the genus Parazygiella which is found in Washington State.
Orb weaver spiders do spin amazing circular silk webs that can appear to float in the air although they always anchored to something. Some orb weavers will just sit in the middle of the web and wait for an flying/jumping insect to get caught in the web. Then they pounce on the prey, bite it to inject toxins and wrap it in a silk bundle. Generally orb weavers are considered beneficial predators of insects. So these spiders are toxic to other insects, but in Washington State they are not toxic to humans. Some of the larger species of orb weavers can bit humans, but only in self defense. The bite will catch your attention, but it is not poisonous. Conserve spiders outside the home, but they may be considered a nuisance pest when they invade the home to get out of the cold weather.
For a little more info on orb weavers see:
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