The term “Manhwa” refers to a South Korean comic, which is heavily inspired by the Japanese manga, but their style is different, where the Japanese are selling manga weekly or monthly, and usually they are black and white.
Despite it being different from manga, there are a lot of famous one, that even got made into anime thanks to Japanese anime publishers.
In manga, if a series become very popular, they usually receive a special, 1-2-page coloured version every now and then.
On the other hand, the “Manhwas” are full coloured comics, which are published on the internet weekly or monthly, but they don’t have printed versions like the manga in Japan.
“Manhwa” has first appeared in the early 2000s.
The style and art were heavily inspired by the Japanese manga industries, which went worldwide, bumping their popularity up to the point where the South Korean fanbase started adapting to the craze.
Thanks to the popularity of the original Japanese manga, “Manhwa” was born in South Korea, spawning multiple spin-offs and original content.
“Manhwa” is not as popular as manga, but they have a somewhat large fanbase all over the world, thanks to their uniqueness and different art/story style.
Since you can find comics like this all over the internet and mostly manga sites like MangaDex, it can be picked up by anyone, relatively easily.