add data description to README

README.md

@@ -6,3 +6,46 @@ language:
 # National Taiwan Normal University Course Catalog
 
 Range: 109-1 ~ 112-1
+
+## Data
+
+Each dataset is an array of objects, each object represents a course:
+
+```ts
+interface Course {
+  serial: number
+  code: string
+  name: string
+  ename: string
+  type: string
+  department: string
+  form: string
+  credit: number
+  duration: string
+  gu_domain: string
+  description: string
+  goals: [goal: string, capability: string][]
+  teacher: string[]
+  schedule: string
+  methods: [method: string, description: string][]
+  evaluations: [weight: number, type: string, description: string][]
+  material: string
+  enrollment: number
+  limit: number
+  schedules: {
+    day: number
+    period: [from: number, to: number]
+    location: string
+    classroom: string
+  }[]
+  programs: string[]
+  comment: string
+  restriction: string
+}
+```
+
+## Copyright
+
+The copyright is owned by National Taiwan Normal University.
+
+Source: <https://courseap2.itc.ntnu.edu.tw/acadmOpenCourse/index.jsp>