It is felt that the creation of the Circle is not created by the man himself but came through the inspiration of Nature itself. The shape of Sun, Full Moon, Eyes are some examples for it.

Some basic things :

There are 3 major parts to remember.

Radius : The straight line drawn to the Circumference of the Circle from the Centre point. Diameter : Diameter is the straight line drawn from one point of the circumference to another point of the circumference through the center point (Origin) . Circumference:

Circumference is the curved line drawn from the origin of the Circle having equal radii. It is evident that so many people from ancient period tried to understand the nature of a Circle. They found the relationship between the Circumference and radius of the Circle. Circumference increases with the increase in Radius or Diameter Pi is the ratio of Circumference of the Circle to its Diameter . The value of Pi (Its value is Constant) is very essential factor to know the Area of a Circle. Finding the Value of Pi is not a simple thing because the measurement of the Circumference is not so easy.

So many people tried to know the value of Pi by

different mathematical methods.

It is believed that the Egyptians and Babylonians were the first persons to estimate the value of pi during the period 2000 B.C. The Babylonians estimated its value as 3+1/8 = 3.125

while Egyptians were calculated it as 3.16045

During the period 1200 B.C. Chinese estimated its value

as 3. In the Bible it is written “....and he made molten Sea, Ten cubits from the one brim to the other; it was round all about, and his height was five cubits: and a line of thirty cubits did compass it about.” This states that the value of Pi is approximately 3.

Archimedes was the great mathematician lived during 287-212 B.C. in Syracuse, Sicily. He calculated the value of Pi as 3.1418. He was recognized as the first person to evaluate the value of Pi theoretically. He used the regular polygon to find the approximate value of Pi. He kept one polygon inscribing in the Circle and another one circumscribing around the circle such that the circumference of the circle should kept between them as shown in the figure. By calculating with Polygons he came to the value that the pi lies between 3 1/9 and 3 10 /71 He used the polygon with 96 sides to give more approximate value (If the number of sides of a regular polygon increased then its shape become Circle). In 17th Century , Van conlen also calculated the Value of Pi to 35 decimal places using this method.

PeriodInventorValue

2000 B.CBabylonians25/8 = 3.125

2000 B.CEgyptian Rhind (16/9)2 =

Mathematical papyrus 3.160493

1200 B.CChinese 3

1000- Indian Shatapatha 339/108 =

600 B.C Brahmana3.13888....

250 B.CArchimedes 223/71 < Pi <

22 / 7 =3.141666

130 A.D Chang Hong 3.162277

150 Ptolemy 377/120 =

3.141666

250 Wang fau142/45 =

3.15555

480Zu Chongzhi 3.1415926

< Pi < 3.1415927

499 Aryabhata 62832/ 20000 =

3.1416

640 Brahmaguptha 3.162277

800 Al Khwarizmi 3.1416

1200 Bhaskara3.14156

1220 Fibonacci3.141818

1400 A.D Madhava 11 decimal places

1424 Jamshid masud AlKashi16 decimal places

1596Ludolph van ceulen 20 decimal places

1615It become papular as 32 decimal places

Ludolphin Number

1699Abraham sharp 71 decimal places

1706John Machine 100 d.p.s

1844Zacharias Dase 248 d.p.s

and Strassmitzky

1853Rutherford 440 d.p.s

1853 Lehmann 261 d.p.s

1874William shanks 707 d.p.s

(He took 15 years to Calculate but all were not correct)

The following persons tried to give more perfect value...