1. The first few digits: The most well-known digits of pi are 3.1415926535…. Infinite and
2. non-repeating: Because pi is an irrational number, its decimal representation goes on forever without a repeating pattern.
3. Calculation records: The current record for the number of calculated digits is over 100 trillion, a number that took billions of dollars to compute and can be seen on the Wikipedia page for Pi.
4.Practical use: For most practical purposes, a few decimal places are sufficient. For example, \(3.14\) is often adequate for general use, while NASA uses about 15 decimal places for interplanetary travel.
5. Calculating to a high degree: To calculate the circumference of the observable universe with atomic-level accuracy, you would only need about 38 decimal places of pi.
Loren Berg's Blog 