Number is a concept that encompasses the various ways that numbers can be used. Throughout history, different cultures have developed their own ways of recording numbers and quantity, from the early days of counting sticks in the palm to the modern day decimal system. While many of these systems share a common base, they differ in the specific symbols that are used to represent them. A good way to think of these systems is as a set of scales, each with its own unique range. Each scale is made up of a group of numbers with its own properties and uses. These number sets are then further divided into subsets based on their characteristics. The following table lists the names, properties and symbols used by each of these main types of numbers.
Integers: The positive and negative whole numbers, from one through ten. They are also called cardinal numbers because they are arranged in order on the number line.
Rational numbers: The real numbers that can be expressed as a fraction where the numerator and denominator are integers. The set of rational numbers includes all of the positive integers and some of the negative ones.
Complex numbers: The real and imaginary parts of a complex number, pq, are distinct from each other and from the quaternions and higher-order rational numbers. The set of complex numbers is a subset of the real numbers.
Ordinal numbers: The finite and infinite Number_i used to describe the order of well-ordered sets. The ordinal numbers are not commutative, so they cannot be added together in the same way as natural and positive numbers.
Surreal numbers: The numbers that are neither ordinary nor rational. They are a subset of the real numbers, and they include the infinitesimals and hyperreals.
It is important to use the correct symbol for each type of number in your writing. This will help you to avoid confusion and make it easier for your reader. When in doubt, always choose the most logical symbol and try to use it consistently throughout your writing. In addition to this, if you use a large amount of numbers in your writing, it is a good idea to have a consistent style for representing them. This may mean using a consistent format for all of the larger numbers in your manuscript or leaving a space between each of the six digits when they are written out in numeral form.
When writing about percentages, it is best to report them as numerals followed by % (or percent). However, if the percentage starts a sentence or if the number is an integral part of a name or other official designation, it should be spelled out. For example, the speed of light is a constant that should be spelled out, as should the percentage of employees who are dissatisfied with their job performance. The only exception to this rule is when the percentage is being cited in a quote and is therefore part of someone else's voice.
