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liquid/_basics/truthy-and-falsy.md
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---
title: Truthy and falsy
description: An overview of boolean logic in the Liquid template language.
---
When a non-boolean [data type]({{ "/basics/types/" | prepend: site.baseurl }}) is used in a boolean context (such as a conditional tag), Liquid decides whether to evaluate it as `true` or `false`. Data types that return `true` by default are called **truthy**. Data types that return false by default are called **falsy**.
## Truthy
All values in Liquid are truthy except `nil` and `false`.
In the example below, the text "Tobi" is not a boolean, but it is truthy in a conditional:
```liquid
{%- raw -%}
{% assign name = "Tobi" %}
{% if name %}
This text will always appear since "name" is defined.
{% endif %}
{% endraw %}
```
[Strings]({{ "/basics/types/#string" | prepend: site.baseurl }}), even when empty, are truthy. The example below will create empty HTML tags if `page.category` exists but is empty:
<p class="code-label">Input</p>
```liquid
{%- raw -%}
{% if page.category %}
<h1>{{ page.category }}</h1>
{% endif %}
{% endraw %}
```
<p class="code-label">Output</p>
```html
<h1></h1>
```
## Falsy
The only values that are falsy in Liquid are [`nil`]({{ "/basics/types/#nil" | prepend: site.baseurl }}) and [`false`]({{ "/basics/types/#boolean" | prepend: site.baseurl }}).
## Summary
The table below summarizes what is truthy or falsy in Liquid.
| | truthy | falsy |
| ------------- |:-------------:|:-------------:|
| true | • | |
| false | | • |
| nil | | • |
| string | • | |
| empty string | • | |
| 0 | • | |
| integer | • | |
| float | • | |
| array | • | |
| empty array | • | |
| page | • | |
| EmptyDrop | • | |