555.

During a stationary shopping trip at Tesco Extra in Penang, I stumbled upon a surprising discovery: a little booklet that is still in production and circulation today. This booklet was once considered the "iPhone" of its time, a must-have "smartbook" for people of all walks of life, including students, street hawkers, and even the infamous "Tontin" dealers and members. People would use this booklet to record financial transactions and other important information.

I have vivid memories of my late parents using this booklet often. My father, a taxi driver, would record his daily earnings in it, while my mother, a freelance seamstress, would note down her income from her sewing job. She would also record her savings and repayment plans when she borrowed money from "Tontin".

Looking back, life was simpler and more straightforward during those times, when the technology of 555 was considered advanced.