Toki Pona is a constructed language first created by Sonja Lang in 2001. It’s been further developed since, with Lang publishing a book about it in 2014, and a supplementary dictionary in 2021. The idea is that it’s an ultra-minimalistic language with a very limited vocabulary (just 120 words according to the 2014 book, and 137 according to the 2021 dictionary). In principle, the vocabulary only consists of the most fundamental building blocks for meaning, and by stringing those fundamental blocks together you can see what more complicated concepts are actually made up of. On the flipside, this makes it a difficult language to discuss complicated topics in. All words are polysemous, i.e. they have multiple meanings. This also means that the exact same concept can be described in Toki Pona multiple ways, depending on how the speaker chooses to break down the concept.
Toki Pona is an isolating language with only 14 phonemes: the five vowels /a e i o u/ and nine consonants /m n p t k s w l j/. It’s usually written in the Latin alphabet, with the spelling exactly as per the IPA representation of the pronunciation. However, there are also two logographic writing systems, where each word gets its own logograph. The more simple one is called sitelen pona (“good/simple writing/drawing”), and the more complicated one is sitelen sitelen (“drawn writing”) or sitelen suwi (“cute writing”). There are also a couple of sign languages based on Toki Pona, toki pona luka (more closely based on it) and luka pona (more loosely based on it).
There are some other offshoots of Toki Pona, sometimes known in Esperanto as tokiponidoj (apparently Toki Pona is particularly popular among Esperantists). These include Toki Ma, which expanded the word list to almost 300 to try to make it easier to discuss a broader range of topics, and a few other offshoots that set out to reduce the word count instead.
It’s hard to know exactly how many speakers Toki Pona has, although it does have a thriving online community on platforms like Discord, Reddit and Facebook. It also has an online wiki , a translation of Minecraft, and some books (largely didactic materials and some translations). In a 2021 online census of the Toki Pona community, 652 people described themelves as knowing Toki Pona, of which 165 said they were “fluent” or “advanced” speakers.