What is the best way to store data in this case?

Question

Programming

Colleagues are arguing how to do it right:
Example:
An expense accounting application stores transactions with the attributes "Amount", "Description", "Expense/Income".
Essence of the question:
Colleague No. 1 claims that there should be two cells of expenses and receipts, in which transactions with an amount and description will lie.
Colleague No. 2 claims that there should be one cell in which transactions with the values ​​\u200b\u200bof "Amount", "Description", "Expense / Income" lie.
Who is right and why? If possible, I would like to read some content on this topic.
PS I'm generally a designer, I just got into this dispute and it became interesting myself

Answer 1

Spanish shame. There are simply no words.
Colleague #1 is right. Colleague #2 should read the database normalization rules.