What Are Non-Alphanumeric Characters? Easy Definitions And Examples

Oluwatosin Michael
Oct 06, 2023 By Oluwatosin Michael
Originally Published on Oct 12, 2021
Informative facts for everyone on what are non-alphanumerical characters.
Age: 3-18
Read time: 5.8 Min

Have you ever been confused about what non-alphanumeric characters are?

Non-alphanumeric characters are those characters or kinds of symbols that appear on the keyboard of a computer, including punctuation and mathematical symbols, these special characters are called non-alphanumeric characters. Those characters, which are not letters or numbers, are non-alphanumeric characters. An asterisk (*) is an example of a non-alphanumeric character.

Non-alpha, or non-alphanumeric, characters are used in several ways like in names and passwords, these non-alphanumeric characters are divided into four categories which are general punctuation, brackets, mathematical symbols, and miscellaneous characters. Some examples of these categories are mentioned below.

General punctuation- ´ (grave accent), , (comma), ! (exclamation mark), * (asterisk), _ (underscore), – (hyphen), ; (semicolon), @ (at-sign), : (colon), ? (question mark), .

(full-stop/period), ‘ (apostrophe) and “ (double quote mark). All these kind of symbol falls under the category of general punctuation. There are many more kinds of characters and symbols that are used as an example of non-alphanumeric characters which are discussed below.

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Examples Of Non-Alphanumeric Characters

There are four categories of non alphanumeric characters which are general punctuation, brackets, mathematical symbol and miscellaneous characters. Some of the examples of general punctuation are discussed above like , (comma), @ (at-sign), (grave accent), * (asterisk) _ (underscore) – (hyphen), !

(exclamation mark), : (colon), ? (question mark), ; (semicolon). (full-stop, period)‘ (apostrophe) and “ (double quote mark).

Examples of brackets include ( (open parenthesis), ) (close parenthesis) { (open brace) } (close brace) [ (open bracket) ] (close bracket) < (less than) > (greater than). Examples of mathematical symbol include %(percent) +(plus sign) =(equals) .

Decimal points and signs of miscellaneous character include ~ (tilde), ^ (carat), | (pipe), / (forward slash), \ (backslash), $ (dollar sign), & (ampersand), # (hash mark).

These were some basic examples of non-alphanumeric characters which are common in usernames and passwords. There are many signs that can be used as non-alphanumeric passwords because non-alphanumeric passwords are made up of a combination of punctuation and symbols and it is possible that your password might contain some special characters, or non-alphanumeric, characters for heightened security.

So, in short, any character on your keyboard which is not a part of the alphabet or is numeric can be considered a non-alphanumeric character.

Examples Of Alphanumeric Characters

Computers or central processing units communicate through the form of numbers with the help of a machine or alphanumeric characters that are used by computer programmers to write their instructions using numbers rather than alphabet characters.

There is a binary code for this kind of work that only uses zeros and ones to represent an alphanumeric character and there is another way that computer programmers can represent the alphanumeric characters, that is by using ASCII (American Standard Code for Information Interchange).

There are in total, 26 characters of the alphabet (from A to Z) and the numbers from 0 to 9 used in alphanumeric characters.

There are two types of examples of alphanumeric characters made by using the combination of special symbols, numbers, and the characters of the alphabet. The letters of these alphabets can be used in lowercase as well as uppercase.

In places like airlines and auto manufacturers both skip the lowercase letter 'i' to avoid confusion with the numeral '1'. The alphanumerical list consists of alphabetic characters A through Z and numeric characters which are from zero to nine.

What is a good non-alphanumeric password?

Nowadays, whenever we login into something we are asked for two things, an email address and password which should be very safe to secure our personal details from others and therefore people use various kinds of passwords made of alphabets, uppercase letters, lower case letters, numerals, different types of digits, and many more.

Just remember that in making a password do not use a space bar or any kind of word which is known to many peoples.

As a requirement of the password, it should be eight digits long and the password must contain a non-alphanumeric character.

A good non-alphanumeric password must contain all the required details asked by the computer and some special characters used such as a comma (,), question mark(?

), ampersand (&), percentage (%), and so on because it is natural that the more difficult your password is the more secure your account will be. Passwords that are more safe are made up of different and unique combinations that use letters, numerals, lower case, upper case, Arabic signs, and numbers.

Passwords are mostly asked by social media sites like WhatsApp, Facebook, Instagram, Twitter, Snapchat, and many more.

What are non-alphanumeric characters used for?

Non-alphanumeric characters are good for making strong passwords.

Non-alphanumeric characters are used as punctuation and are treated as white space. Still, people get confused with alphanumeric and non-alphanumeric characters but it is clear that they are used in making passwords as they ask for any non-alphanumeric character which may keep the password more secure and ensure you proper safety for your social media or any other account.

These are the combination of symbols and punctuation as they may be used for heightened security of your personal information before you share it with others.

These are strings and are divide into four categories that are general punctuation, brackets, mathematical symbols, and miscellaneous characters. But in these symbols which are treated as white space do not preserve word order in a multi-word search.

Therefore if a kind of symbol character is adjacent to a punctuation character, the symbol character will be ignored but still the symbol character and the punctuation character are treated equally and the same in the punctuation string alone and on their own.

Why do non-alphanumeric characters create good passwords?

Non-alphanumeric characters create good passwords as they make use of symbols and punctuation which is very difficult to break if someone tries to hack your account. It is for their heightened security which is mostly used in our social media account as this was a comment by people who have used this before.

They make use of numerals, Arabic signs, upper case letters, numbers, and lower case letters as these can secure your account perfectly. Therefore nowadays people prefer using passwords on the computer using non-alphanumeric characters.

Most of the sites require passwords with a minimum of 8-12 characters in them and they should be unique as well as strong, passwords that are formed in a different and unique manner are considered as strong ones, or else the site will say to change it as soon as possible and there are various tools available nowadays to create unique passwords.

Hackers these days have become professional in cracking passwords and taking out your personal information therefore it is necessary to make strong passwords either by yourself or with the help of any strong password-making tool.

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Written by Oluwatosin Michael

Bachelor of Science specializing in Microbiology

Oluwatosin Michael picture

Oluwatosin MichaelBachelor of Science specializing in Microbiology

With a Bachelor's in Microbiology from the Federal University of Agriculture, Abeokuta, Ogun State, Oluwatosin has honed his skills as an SEO content writer, editor, and growth manager. He has written articles, conducted extensive research, and optimized content for search engines. His expertise extends to leading link-building efforts and revising onboarding strategies. 

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