Real numbers are thus called continuous. There is no break between them. Consider numbers like $$1,\, 2,\, 3,\, \ldots$$. They don't have any decimals.
Consider two integers $$2$$ and $$10$$. Between $$2$$ and $$10$$, you can find the integer $$6$$. Between $$2$$ and $$6$$, you can find the integer $$4$$.