Underscore Symbol (_) – How to Type on Keyboard
The underscore symbol (_) is one of the most widely used characters on the keyboard, yet it often confuses people. Known by many names — underscore, low dash, guion bajo (Spanish), barra baja (Spanish), tiret du bas (French), unterstrich (German) — it plays an important role in writing, computing, filenames, programming, and online communication.
This guide explains the underscore meaning, definition, symbol, synonyms, and practical usage so you’ll never be confused about it again.
What Is an Underscore?
An underscore is a horizontal baseline character (_) primarily used to bridge text or substitute for spaces when actual spaces are technically restricted. Unlike standard letters, the underscore symbol sits entirely below the baseline of neighboring text.
Underscore Symbol Representation
- ASCII:
95 - Unicode:
U+005F - Typographic name: “Low Line”
- Need the underscore symbol for a filename, username, document, or code snippet? Copy this character:
_
Underscore Meaning in Everyday Use
The meaning of underscore depends on context:
- Computing: Replaces spaces in filenames or usernames (e.g.,
my_resume.pdf). - Text formatting: Historically used on typewriters to “underline” words (e.g.,
_word_). - Emphasis in writing: Underscoring means placing importance on something (“This underscores the importance of clarity”).
- Placeholder characters in forms and passwords (e.g.,
____) - Programming: Used in variable names (
user_name) and as a special symbol in languages like Python (__init__).
How to Type Underscore (Keyboard Shortcut & Device Tips)
The underscore shares a key with the hyphen (-) on most keyboards. Unlike the hyphen, typing an underscore requires holding the Shift key.
On Desktop (Windows & Mac)
- Shortcut: Press and hold
Shift+Hyphen (-) - Location: The key is situated directly to the right of the zero (
0) key on standard QWERTY layouts.
On Mobile Devices (iOS & Android)
- Tap the
?123(or numeric) key to switch to the numbers layout. - Locate and tap the
_symbol. On some layouts, you may need to tap an additional symbols page (=\<or1/2).
Underscore Symbol on Keyboard
Since it requires the Shift key, beginners often confuse it with hyphen. Remember:
-(hyphen) = without Shift._(underscore) = with Shift.
Underscore vs Hyphen – When to Use Which
People frequently mistake the underscore symbol for the hyphen. While they often share the same physical key, they serve entirely different purposes.
Visual Difference
- Hyphen (-): Short, placed mid-text.
- Underscore (_): Longer, placed below text.
Usage Differences in Writing
- Hyphen: joins words or breaks syllables (well-known, long-term).
- Underscore: Rarely used in formal writing.
In Technology
- URLs – Hyphens are strongly recommended and treat hyphens as word separators but not underscores.
- Example:
file-name.html(good) vsfile_name.html(less ideal).
- Example:
- Filenames & Usernames: Underscores are more common, especially where spaces are not allowed.
Underscored and Underscoring Meaning (Verb Usage)
The word underscore is also used as a verb in English.
- Underscored meaning: Something that was emphasized or highlighted.
- Example: “The study underscored the dangers of pollution.”
- Underscoring meaning: The act of emphasizing.
- Example: “She kept underscoring the importance of practice.”
Underscore Synonyms in English and Other Languages
The underscore has many synonyms depending on the context or language.
- English: Low line, low dash, horizontal bar, underscore sign
- Spanish: Guion bajo, barra baja
- French: Tiret du bas
- German: Unterstrich
- Chinese: 下划线 (xià huà xiàn)
How to Insert an Underscore in Google Docs
If your keyboard shortcut isn’t working, you can manually insert the underscore symbol within Google Docs:
- Type the text that you want to underscore.
- Now go to “Insert” → “Special characters“
- Type “low line” in the search box
- Select the “Underscore” from the list to appear in Google Docs
How do I type an underscore?
Press Shift + Hyphen (-) on Windows/Mac. On mobile, use the symbols keyboard.
Is underscore same as hyphen?
No. A hyphen (-) is short and sits in the middle of a text line to connect words. An underscore (_) is longer, sits at the bottom baseline, and is used primarily in tech, URLs, and coding environments.
What is the meaning of the underscore symbol in a text?
In text-based digital messaging (like Slack or Discord), wrapping a word in an underscore (e.g., _text_) is often used as a formatting shortcut to apply italics or emphasis to that specific word
Other keyboard symbols worth knowing: backwards 3, bullet point, and plus-minus (±).