The "end of the world" is mentioned frequently. It could refer to one of two different things.

The most common interpretation is that it refers to the end of the literal world when Yahu Yahweh (the Messiah) comes in the clouds at His second coming.

However, that ISN'T the end of the world. The world continues for another 1000 years (the millennium) when it is finally re-created. It could refer to the end of the people, but that isn't right either. They are still on the earth (dead) and will be on the earth (alive again) after the millennium. The earth has not ended.

Note: "end(s) of the earth" is a geographical reference, not a time reference. Occasionally the Hebrew "'erets" is translated as "world" instead of "earth", but is the same word as "earth" and is still geographical.

"End of the world" actually refers to the "end of the age". The ending age MAY be the age that ends at Christ's 2nd coming, but their are numerous other ages that will also end, so we have to determine WHICH age is ending. The following verses prove this:

Hebrews 9:26
For then must he often have suffered since the foundation of the world (kosmos): but now once in the end of the world (aion - eon - age) hath he appeared to put away sin by the sacrifice of himself.

The first instance of "world" actually means "world" (kosmos). The second instance is translated from "aion" and means "eon" or "age". How do we know this? Because WHEN Yahushua conquered Satan, it was NOT the end of the (physical) world, but instead was the end of an age. It was the end of the age in which Satan was prince of this world. Christ defeated Satan and regained His position as Ruler, becoming the King! It was the start of the age (eon) of the Kingdom of Heaven!

Matthew 13:39-40 King James Version (1769)
The enemy that sowed them is the devil; the harvest is the end of the world; and the reapers are the angels. As therefore the tares are gathered and burned in the fire; so shall it be in the end of this world.

Here, again "world" is "aion" in the Greek and should have been translated eon or age. It is translated correctly by Young:

Matthew 13:39-40 Young's Literal Translation (1898)
and the enemy who sowed them is the devil, and the harvest is a full end of the age, and the reapers are messengers. `As, then, the darnel is gathered up, and is burned with fire, so shall it be in the full end of this age,

Notice that in the King James Version, the harvest is at the end of THE world, but the "so shall it be" is in the end of THIS world. This world compared to what other (that) world? Young makes sense of it. The harvest is at the end of THE age and the "so shall it be" is the end of THIS age just mentioned. In either instance the author COULD have used the word "kosmos" if he meant the physical "world".

All the other New Testament references to the "end of the world" are actually the "end of the age".

Likewise, the Old Testament with the Hebrew word "owlam":

Isaiah 45:17
But Israel shall be saved in Yahweh with an everlasting (5769 `owlam) salvation: ye shall not be ashamed nor confounded world (5769 `owlam - time out of mind - an age) without end.

Isaiah 45:17 Young's Literal Translation (1898)
Israel hath been saved in Jehovah, A salvation age-during! Ye are not ashamed nor confounded Unto the ages of eternity!