'Noon' means 'midday' or 12 o'clock during the day. 'Midnight' refers to 12 o'clock during the night. Simple right? Well, maybe not, especially if you're using a 12-hour clock. When most people say 12pm, typically they're talking about the middle of the day: 12 noon.
As the day begins at midnight, midnight must be 12am. The moment of noon is in the first second, consequently minute and hour of the afternoon therefore noon must be 12pm.
So technically, 12AM and 12:30PM is just afternoon, which technically is 12PM. So to avoid confusion, many people do not use 12AM or 12PM, and prefer to use midnight for 12AM and noon for 12PM. So afternoon begins at noon, and runs until evening.
The universal convention is that 12:00 AM signifies midnight, and every moment afterward is also 'AM' until the precise moment of 12:00 PM which is midday.
'Noon' means 'midday' or 12 o'clock during the day. 'Midnight' refers to 12 o'clock during the night.
There are no standards established for the meaning of 12am and 12pm. It is often said that 12am Monday is midnight on Monday morning and 12pm is midday.
For example, “Good morning” is generally used from 5:00 a.m. to 12:00 p.m. whereas “Good afternoon” time is from 12:00 p.m. to 6:00 p.m. “Good evening” is often used after 6 p.m. or when the sun goes down. Keep in mind that “Goodnight” is not a salutation.
This is the middle of the day, also called "NOON" (12:00 hours). This is the time from midnight to midday. This is the time from midday (noon) to evening. From 12:00 hours to approximately 18:00 hours.
The word noon is derived from Latin nona hora, the ninth canonical hour of the day, in reference to the Western Christian liturgical term none, one of the seven fixed prayer times in traditional Christian denominations.
12 o'clock in the middle of the day; noon: He frequents the restaurant at noontime.
To determine when it's noon (without a watch or radio) place a stick at the southernmost end of your north-south line. Use a plumb line to make sure that the stick is vertical. When the shadow cast by the stick crosses the north-south line, it's noon.
Afternoon is often defined as the period between noon and evening. If this definition is adopted, the specific range of time varies in one direction: noon is defined as the time when the sun reaching its highest point in the sky, but the boundary between afternoon and evening has no standard definition.
Finding your "Local Noon"
"Local Noon" occurs when the Sun is seen exactly in the South direction. Strictly speaking, "Local Noon" is the exact time when the Sun reaches its highest point in the sky. This is also the time that it crosses the vertical, imaginary line, that astronomers call the "meridian".
Morning is the period from sunrise to noon. There are no exact times for when morning begins (also true of evening and night) because it can vary according to one's lifestyle and the hours of daylight at each time of year. However, morning strictly ends at noon, which is when afternoon starts.
12 a.m. is midnight. 12 p.m. is midday. After 12 a.m. it is morning. After 12 p.m. it is afternoon.
The 24 hour clock dispenses with this, but to avoid any possibly confusion over which day, the military has a convention in which midnight is 23:59. Simply, lunchtime is 12 noon.
As standard 12:00 AM is taken as the start of the day. Time of the day is divided in two halves (24hour= 12 hours before midday + 12 hours after midday) so the 11 AM is 11th hour before midday as clock strikes 12 again it changes to PM (after midday) so it's 12 PM after 11 AM and 12 AM after 11 PM.
12 a.m. is night (or the beginning of the next day). 12 p.m. is the beginning of the afternoon.
The word noon comes from a Latin root, nona hora, or "ninth hour." In medieval times, noon fell at three PM, nine hours after a monk's traditional rising hour of six o'clock in the morning. Over time, as noon came to be synonymous in English with midday, its timing changed to twelve PM.
Noon would come at the same clock time every day. But the Earth does orbit the Sun; so in those same 24 hours, it has also moved about a degree forward in its orbit. That orbital motion has an effect on the length of the solar day. Imagine for a moment that the Earth only orbits the Sun and does not rotate on its axis.
Noon is the time exactly halfway through the day (12.00-12:00 in the 24-hour clock and 12:00 PM-12:00 PM in the 12-hour clock). Midday also means noon, although this also means around noon, or very early afternoon.
Is noon a.m. or p.m.? Well, the correct answer may surprise you because it is actually neither. That's right; technically noon is neither a.m. nor p.m. Although it is common to see noon expressed as 12:00 p.m., it is actually incorrect.