payment

1. e payment

1.1. history

1.2. advantage

1.3. kinds

1.4. something need to prove

1.5. future

2. how will e payment change us

2.1. the way we buy

2.2. the way we sell

2.3. the way we think

3. paper

3.1. history

3.2. advantage

3.3. kinds

3.4. problem

4. barter

4.1. reason

4.2. disadventage

4.3. history

5. commodity

5.1. history

5.2. kinds

5.3. function

5.4. problem