How to insert an image in html email?

Question

css

Drafted a letter. The pictures I use are now neatly stored in the /images folder. How to send a letter so that these pictures appear at the recipient? There is a thunderbird, but it only turned out to send a layout without pictures.

Answer 1

Make image URLs absolute example.com/image.jpg

Answer 2

Convert pictures to base64.
But there is also a minus here - for example, Google Mail does not understand this format