When does total solar eclipse occur?

Hint: A total eclipse happens when the Moon's dark silhouette totally obscures the Sun's intensely bright light, revealing the much fainter solar corona. Totality happens only in a restricted track on Earth's surface during any given eclipse. The road of wholeness is the name given to this tight path.

Complete step-by-step solution:
When the new moon passes between the sun and the earth, a total solar eclipse occurs.
There are five phases to a total solar eclipse:
The partial eclipse starts: This is the first time the moon appears to be visible above the sun's disc.
Beginning of the total eclipse: This is the second time the sun is entirely obscured by the moon. The sun takes on the appearance of a diamond ring.
Maximum eclipse and total eclipse: This is the time when only the sun's corona is visible. The entire sky darkens at this time, and there is a potential that the temperature may drop. When the moon begins to move away from the sun, the total eclipse comes to an end.
Partial eclipse ends: At this point, the moon has stopped concealing the sun and the eclipse has come to an end.

Note:Total solar eclipses are visible on Earth due to a fortunate set of circumstances. Even on Earth, the variety of eclipses that people are familiar with now is a transient (on a geological time scale) occurrence. The Moon was closer to the Earth hundreds of millions of years ago, and hence appeared larger, hence every solar eclipse was total or partial, and there were no annular eclipses.