The meter, symbol m, is the SI unit of length. It is defined by taking the fixed numerical value of the speed of light in vacuum c to be 299 792 458 when expressed in the unit m s-1, where the second is defined in terms of ΔνCs. The kilogram, symbol kg, is the SI unit of mass.
The metre is currently defined as the length of the path travelled by light in a vacuum in 1299 792 458 of a second. The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole along a great circle, so the Earth's circumference is approximately 40000 km.
You take 3 steps east, turn around & take another 7 steps west (4 steps always from origin) you turn around again and take 6 more steps east - 2 steps always from origin
