create image in shopify.

//Display the image in shopify.
Before display the image, you have to upload the image on shopify.

{{ 'logo.png' | asset_url | img_tag: 'The Soap Store' }}

output:

<img src="//cdn.shopify.com/s/files/1/0222/9076/t/10/assets/logo.png?796" alt="The Soap Store">

add class to img

{{ 'logo.png' | asset_url | img_tag: 'The Soap Store', 'css--class1 css--class2' }}

output:

<img src="//cdn.shopify.com/s/files/1/0222/9076/t/10/assets/logo.png?796" alt="The Soap Store" class="css--class1 css--class2">

CREATE YOUR OWN IMG  TAG

<img src="{{ 'logo.png' | asset_url }}" alt="The Soap Store" class="css--class1 css--class2" id="logo">