Replaced principals with principles (#6739)

sites/website/src/docs/introduction.md

@@ -83,7 +83,7 @@ FAST is a collection of technologies built on Web Components and modern Web Stan
 
 ### How does FAST leverage Web Components?
 
-One of FAST's driving principals is "strive to adopt open, web standards-based approaches as much as possible." To that end, FAST is built directly on the W3C Web Component standards mentioned above, and does not create its own component model. This allows components built with FAST to function the same as built-in, native HTML elements. You do not need a framework to use FAST components, but you can use them in combination with any framework or library of your choice.
+One of FAST's driving principles is "strive to adopt open, web standards-based approaches as much as possible." To that end, FAST is built directly on the W3C Web Component standards mentioned above, and does not create its own component model. This allows components built with FAST to function the same as built-in, native HTML elements. You do not need a framework to use FAST components, but you can use them in combination with any framework or library of your choice.
 
 ### How can FAST help me?