When the dimensions are infinitely large then straight lines take the form of curve. In this situation a square may take the form of a circle.
Leading Lines take many forms. They make lines that make up the picture. It could be a railroad track, it doesn't matter. Leading Lines do exactly that.
There are an estimated 40 million source lines of code in Windows XP.
16KB, or 16384 bytes, can be addressed with 14 address lines. (214 = 16384)
10
Many Years. Many Years.
Standard answer seems to be 50 million.
5 droplets form a raindrop.
1.
One Billion!
Many of them have their own emergency generators, ready to take over if the commercial power fails.
Mountains are most often formed on faults. Because these faults occur due to the space between tectonic plates, these faults take the form of lines. Thus, the thin belts are along these long lines.