This is hexadecimal notation for rgb. Each character represents 2 bytes, which encode a value from 0 to 255.
This is a bit more confusing because this is a shorthand notation: you’d actually need 2 hexadecimal characters for 2 bytes (eg #0077ff would be rbg(0, 127, 255)). In this shorthand notation, I think there’s an implied 0 (eg #07f is #0070f0).
So you can’t represent all rgb colour with only 3 characters, but for this use-case it’s fine.
In css you can use either of these 3 notations, for example
> The format of an RGB value in hexadecimal notation is a '#' immediately followed by either three or six hexadecimal characters. The three-digit RGB notation (#rgb) is converted into six-digit form (#rrggbb) by replicating digits, not by adding zeros. For example, #fb0 expands to #ffbb00. This makes sure that white (#ffffff) can be specified with the short notation (#fff) and removes any dependencies on the color depth of the display.
I'm quite fond of the 3-digit hexadecmial RGB notation. It's a concise way to express the colours I use for web pages or Emacs font locking. In these cases, I rarely need the full 16-million-colour range offered by 6 digits. The 3 digits are usually more than enough, at least to me.
Every tool I've ever used referred to this as hex (including design tools but maybe I'm sheltered), whereas rgb refers to the 0-255 triples
If someone asked me for a colour in "RGB" they'd be rightly confused if gave them a hex format colour (obviously you can convert between them but that's not what they asked for)
It's a shortened form of hex colors from CSS, but it does correspond to RGB since the first character of the hex value is the R, the second character is the G, and the third is the B. So for instance, a hex value from this game of #F18 means the red is F (out of F), the green is 1 (out of F), and the blue is 8 (out of F).
williamdclt|8 months ago
This is a bit more confusing because this is a shorthand notation: you’d actually need 2 hexadecimal characters for 2 bytes (eg #0077ff would be rbg(0, 127, 255)). In this shorthand notation, I think there’s an implied 0 (eg #07f is #0070f0).
So you can’t represent all rgb colour with only 3 characters, but for this use-case it’s fine.
In css you can use either of these 3 notations, for example
susam|8 months ago
From <https://www.w3.org/TR/CSS1/>:
> The format of an RGB value in hexadecimal notation is a '#' immediately followed by either three or six hexadecimal characters. The three-digit RGB notation (#rgb) is converted into six-digit form (#rrggbb) by replicating digits, not by adding zeros. For example, #fb0 expands to #ffbb00. This makes sure that white (#ffffff) can be specified with the short notation (#fff) and removes any dependencies on the color depth of the display.
I'm quite fond of the 3-digit hexadecmial RGB notation. It's a concise way to express the colours I use for web pages or Emacs font locking. In these cases, I rarely need the full 16-million-colour range offered by 6 digits. The 3 digits are usually more than enough, at least to me.
siriusfeynman|8 months ago
If someone asked me for a colour in "RGB" they'd be rightly confused if gave them a hex format colour (obviously you can convert between them but that's not what they asked for)
jenadine|8 months ago
joemi|8 months ago