Small numbers (from one to nine) should be spelled out.

It is generally recommended to write cardinal numbers up to ten in words, except when telling the time.

Numbers above ten are usually written using numerals rather than words.

When a number begins a sentence, spell it out in words, regardless of its value.

However, when the number at the beginning of the sentence denotes a year, you can use numerals.

Ordinal Numbers should be written in words, except when you are writing out dates.

Consecutive numbers can look slightly confusing to the reader. To avoid this confusion, always spell out one of the two numbers. For example:

You can use numerals to express time:

But, some people spell out the time and use o'clock.

When expressing dates, use figures.

Decades can be expressed both in written forms and figures. When you want to write decades in figures, put an apostrophe before the incomplete numeral and no apostrophe between the number and the 's'.

You can also write out decades in complete numerals. But again, do not put an apostrophe between the year and the 's'.

When you are writing out sums of less than a dollar, you do not need to use a decimal point or a dollar sign.

When you use a dollar, euro, or pound symbol, do not add the word 'dollar, euro, or pound' after the number.

When writing out a three or more digit number, it is not necessary to use the word 'and'. But, you can use 'and' to express decimal points accompanying these numbers.

In technical writing, it is recommended to express numbers used with measurements of time or distance using figures rather than words.

Normally, any number that expresses an important value must be written in figures. When the number is not very important it can be written in words.

Write out fractions and use hyphens and the word 'and' to separate the numbers.

Units of measurement should always be expressed as numerals.

To read the decimal numbers, after the decimal point, we should read out numbers digit by digit, not as a compound number.

Remember that in English, a decimal point is used for decimal numbers and a comma is used to separate thousand:

Roman numerals originated in ancient Rome and are still used for writing numbers. Numbers in this system are expressed by combinations of letters from the Latin alphabet.

All the numbers in the Roman numeral system are made from only seven symbols. With these seven symbols, you can write every number you want.

Different arrangements of these seven symbols represent different numbers. For example:

We can put the symbols in descending order from left to right and add numbers together. If we add all of the numbers' values together, we get the represented number. For example:

We can also put the symbol with a smaller value on the left side of the one with a larger value and subtract the value of the smaller symbol from that of the larger symbol to get the total value. For example:

Take a look at the table below to see more examples:

In English, to tell a phone number, we need to say every number individually. Let's see an example:

If there is a 'zero' in the phone number, it is more commonly expressed as 'oh' instead of 'zero'.

If there are two numbers repeated in the phone number, we can say "doube+number". And if the number is repeated three times we can say "triple+number".

To say the number of apartments (this can be an apartment number, villa number, hotel room number, house number, or even a street with more than two digits number), first we need to look at the last two digits. When the number has only two digits, we say the number like the following examples:

If the number has three digits, we can either say each digit individually or say the first digit alone and the last two digits in pair; the second way is more common:

If the number has four digits, we read them in pairs, we can also say them digit by digit.

In case there are zeros in the number, the rules change. If the last two digits are zeros, we cannot say them separately. Therefore, we will do as the examples:

If the three-digit number has zero in the middle, we need to say the numbers digit by digit, and we pronounce the zero as 'oh'.

If in a four digit-number, the second to the end number is zero, we say it as the following: