Unidirectional (one-way) data flow

• You pass data down from parent to child component
• You can't update parent's state from a child
  • Instead, you handle events dispatched by a child to update the state
• Parent -> Child

Bidirectional (two-way) data flow

• Parent and child components share the data
  • Change to model updates the view
  • Change to view updates the model
• Parent <-> Child

Resources

• Thinking in React
• Angular: Two-way binding
• Vue.js: State Management
• Vue.js: One-Way Data Flow
• Vue.js: v-model (two-way binding)
• StackOverflow: difference between one-way and two-way data binding