Underscore | When to use underscore in variable names

When can I use underscores in email addresses?

First off, the underscore is a versatile punctuation mark that can be used in a variety of ways. It can be used to join words (e.g., "a_b"), create emphasis (e.g., "a__b__c"), or indicate a space (e.g., "a_ b"). But how and when do you use it?

Generally speaking, underscores are allowed in email addresses. However, usage of underscores differs from one email provider to the next. For example, many large providers like Gmail, Yahoo and Hotmail do not allow email addresses to contain underscores. In addition, some services may place restrictions on which characters can be used in your username or address in general, meaning you may have trouble creating an address with underscores if it’s not supported.

That being said, you will still find plenty of smaller providers that allow underscores in emails – for instance ProtonMail and ConvertKit both permit their users to include them in their addresses. It is important to note though that while you might have an underscore included in your address at sign-up time with these providers, they don’t guarantee that all sent emails will arrive properly if they contain underscores.

Another point worth considering is that some servers may strip out underscores from incoming emails before delivery making them impossible to retrieve even if received successfully by the recipient’s inbox. This means it’s best to avoid using them when signing up for a new account or sending a message for the first time unless you know the provider supports this character without any issues.

Can I use underscores in URLs?

Yes, underscores are allowed in URLs. The underscore character (_) is a valid character in URLs and can be used as part of the path or filename of an address. This means that whenever you’re linking to another web page, image or file, you can add an underscore either as part of the path to the resource or directly within its name.

It is important to note though that some browsers may not correctly render links containing underscores. Therefore, if you decide to use them when creating a URL keep in mind that it might not open correctly for some users depending on their browser settings.

You should also try to avoid using underscores when constructing your main website address; instead opting for hyphens (-) as a common best practice for both SEO and user experience reasons. Hyphens are easier to read and generally more recognizable than underscores; making them better suited for front-facing web addresses.

Can I use underscores in domain names?

While underscores have become more accepted as part of domain names, they are still treated differently from other characters when registering a website or sending an email. Generally speaking, underscores can be included in domain name strings, but their use is often restricted by the selected service provider.

For example, many of the popular registrars do not allow you to register a new domain that contains underscore characters. Although some might permit them when creating a subdomain like mail_server.example.com, they won’t work if you try to create an address with multiple underscores such as news__updates.example.com.

It is also worth noting that some web hosting companies may not support domains containing underscores in their default configuration so it’s best to double-check with your provider before investing any time and money into the project. This can save you headaches further down the line if hidden problems start showing up once everything has been set up on the server side of things.

Is an underscore a special character?

In various contexts, an underscore (_) can be considered both a special character and a standard character. In programming languages, underscores often serve as special characters with specific meanings, such as in variable or function names. They can denote word boundaries or placeholders in certain syntaxes. However, in file naming conventions, underscores are treated as standard characters. They are commonly used as substitutes for spaces in file names, facilitating compatibility across different platforms. Nevertheless, in web addresses (URLs), while underscores are technically allowed, they are generally discouraged due to potential readability and compatibility issues. Thus, whether an underscore is regarded as a special character depends on the specific context in which it is being used, with its significance varying across programming, file naming, and web address conventions.

Are underscores necessary in filenames?

Underscores are often used in filenames to separate words. Using underscores in a filename makes it easier to read, especially if the name consists of multiple words. Underscores can also be used to make the file more organized, as they make it easier to identify what type of file it is and where it should go. Additionally, underscores are sometimes used in filenames to replace spaces, which can increase compatibility with devices and operating systems that don't support spaces within filenames.

What are the issues with using an underscore in apps?

It is possible to run into issues with underscores when using certain applications that are not designed to handle them. For example, if you are entering a directory path in a command prompt window, it can be difficult to enter an underscore because the character is typically used as a shortcut for a specific action. Additionally, some programs do not recognize underscores as valid characters in filenames and will either cash or give an error message when they encounter one.

How do I underscore a letter?

To underscore a letter, you can press and hold the Shift key while pressing the dash (-) key. This will create an underscore character below the letter. For example, _A would produce an A with an underscore underneath it. Additionally, some programs allow you to insert symbols using the Insert Symbol feature (e.g., Microsoft Word).

When do I use an underscore in variable names?

The underscore character is often used in variable and function names in programming languages. This allows programmers to create more meaningful, readable names for objects and functions, rather than using camelCase or other syntax. For example, instead of "getNumber", a variable could be named "_getNumber" to emphasize its purpose as a retrieval function. It is also used in computer filepaths as a separator between two words or phrases.