A solar eclipse occurs when the Moon passes between Earth and the Sun , and totally or partly obscures the image of the Sun for a viewer on Earth. A total solar eclipse occurs when the Moon’s apparent diameter is larger than the Sun, blocking all direct sunlight, turning day into darkness.
On Friday morning, 92% of the Sun will be covered in an almost total eclipse!
(This information is from http://astronomy.ie/solareclipsemarch2015.php)
NB:Looking at the Sun is dangerous and can result in serious and permanent damage to the eyes. The only way to look at the Sun is indirectly or through a filter.
See an interesting video on solar eclipses here: https://youtu.be/_201ttTSG30