AM and PM Full Form- What is AM and PM full form?

AM and PM are two commonly used words used whenever denoting time. Have you wondered what the full form of AM and PM is? Where did these terms come from? If your answers are yes, you are at the right place. Before moving on to understand the whole concept of AM and PM, let's first have a look at AM full form and PM full form. The full form of AM is Ante Meridiem while the PM full form is Post Meridiem. These terms are used in the 12-hour clock system to make it easier to read the time. Continue reading to get more details on AM and PM and the clock system.

What is AM and PM Full Form?

The full form of AM is Ante Meridiem and the full form of PM is Post Meridiem. Both of these are Latin words used to represent the time for Before Noon and Afternoon respectively. These are also written as A.M. and P.M. In the 12-hour clock system, AM means "before midday" and PM means "after midday". 

How AM and PM Full Form Got Their Names?

• Meridiem means "Midday"
• Ante means Before
• Post means After

So:

AM full form is Ante Meridiem, which means "before midday"

PM full form is Post Meridiem, which means "after midday"

Importance of AM and PM

AM and PM today are not just two terms. In countries like India, the United States, Australia, New Zealand, etc. where people follow a 12-hour timekeeping system, the easiest way to understand the time before noon and afternoon is through AM and PM. 

Just imagine, someone says to you let's meet tomorrow at 9 O'clock and does not mention morning or evening. Won't it get difficult for you to understand what time to go to meet? Now, if someone says let's meet tomorrow at 9 AM, it is clear that the person wants to meet in the morning. The 12-hour time system with AM and PM clears such confusion.

History of AM and PM

AM and PM are not modern terms used to denote time. The invention of the sundial resulted in the use of A.M. and P.M. in 1500 B.C. in ancient Egypt. The credit for dividing the day into hours or 24 parts goes to the Egyptians. The sundial in ancient times was popular for knowing the time using the position of the sun in the sky on the sundial. In today's 12-hour time zone, AM covers the time from midnight to noon while PM covers the rest of the 12 hours from noon to midnight. The concept of AM and PM gained more popularity in the 19th century with the increased use of clocks. 

Countries Where AM and PM are More Popular

All the countries that follow the 12-hour clock system use AM and PM. Some of these countries are:

• India
• The United States
• The Republic of Ireland
• Pakistan
• Malaysia
• New Zealand
• Malta
• Bangladesh
• Mexico
• Philippines

Fun Fact about AM and PM

• The 12-hour clock system was used in ancient Babylon first and then it was followed by the Ancient Greeks. 
• The 12-hour clock system is not something very new. It was used in ancient times by Egyptians and Mesopotamians in primitive forms. 
• In the tomb of a Pharaoh, for daytime use Egyptian sun-dial clock was found while for night-time Egyptian water clock was found. 
• Technically, there is no 12 AM or 12 PM. These are actually called 12 in noon for 12 PM and 12 at midnight for 12 AM.
• There is no AM and PM concept for countries like Canada where the 24-hour clock system is followed.