Language Learning Terms
Some useful terms below. I will not define comprehensible input and related terms in depth here, as I already did that on this post (I will summarize on this post though).
Comprehensible Input generally is anything you understand the main idea of - literally anything. It's any experience in the language you understand. (So textbook dialogues with translation and grammar notes to explain what the dialogue means, conversations where someone gestures to get the main idea across, cartoons for toddlers where the visuals make what's happening clear, bilingual texts, learner podcasts with translations or explanations, graded readers, CI Lessons, etc... and then once you understand more of the language, most things become comprehensible input as you understand more things).
Comprehensible Input Lessons are TRPS lessons, Learner Podcasts, Graded Readers, and anything designed to be completely understood to a learner for their level of knowledge, typically CI Lessons for beginners are audio-visual lessons where all of the meaning can be understood from the visuals alone - Dreaming Spanish is an example, or the teacher provides a short word list-summary of things the learner needs to understand to follow along - Lazy Chinese is an example.
Automatic Language Growth is a theory of language learning Marvin Brown came up with, and he made an ALG Thai school that followed the theory. ALG theory is that people learn language only by meaningful experiences in the language. And that any explicit study, any thinking about the language features, or speaking or reading before you have a good grasp of the language, causes issues. ALG Lessons are a subset of CI Lessons, stricter requirements for ALG Lessons as they MUST be entirely in the target language and must not contain text until the learner is higher level, must not ask the learner to speak until they're a high level, and must not contain translations. ALG Lessons are Comprehensible Input Lessons, but CI Lessons are a broader category of things. The general term comprehensible input is even broader still, as it is anything you can understand the main idea of in the language you are learning.
CI Method - this is how Dreaming Spanish learners tend to refer to Dreaming Spanish's method of learning. The method is ALG, with some relaxing of the ALG recommendations. The method can be boiled down to: you learn by extensive listening to CI Lessons (particularly ALG Lessons if you're being strict about ALG), and by extensive listening to Learner Podcasts (particularly ones that use zero translations if you're being strict about ALG), and then eventually extensively listening to media made for native speakers that you can understand the main idea of. So the entire "learn by only comprehensible input" learning method is to learn entirely by extensive listening to stuff made for learners, then stuff made for native speakers, that you can understand.
Learner materials/materials made for learners - any learning material designed with a learner in mind. So graded readers made for learners who know X amount of words, learner podcasts made for learners who are beginner/intermediate/advanced, CI Lessons made for beginners with many visuals, CI Lessons made for intermediate learners where they assume the learner knows X words, dialogues with translations, textbooks, podcasts that include explanations of new words and grammar, classes. Usually a learner material will contain whatever it expects you to need - so if it's made to be studied intensively then the material will include any translations and explanations it expects a learner at that level to need, and if it's made to be studied extensively then it will use mostly stuff it expects the learner at that level to already know and enough context to guess/figure out the unknown bits.
Extensive - this word is used to refer to extensive listening and extensive reading. All it means is that you listen or read without looking anything up, without relying on any explanations or needing any language learning tools to help. Extensive reading is what you do in your native language now, any time you read. Extensive listening is what you do in your native language now, any time you listen. Extensive reading or listening is usually done with things you understand the main idea of, because it can be frustrating if you do NOT understand at least that much. Typically learner material that is made to be read extensively uses 95-98% words they expect you to understand already, as if you know less words than that you tend to feel frustrated reading extensively.
Intensive - this word is used to refer to intensive listening and intensive reading. All it means is you look up words/explanations/use aids to understand something. You usually look up at least enough unknown words/grammar to understand the main idea, you may look up every single unknown word if you want to. You did this in your native language back in school, when your textbook would define a bunch of terms for you in a glossary and you had to read the definitions before you could read the chapter. You needed to read those definitions, to understand the chapter. Intensive reading is just doing the same thing, in new languages. Some intensive reading materials are already-made for intensive reading with ease: Parallel texts, Graded Readers with vocabulary lists you must read in advance, a learner podcast episode with a list of vocabulary translations in the summary (or that translates when speaking when they figure the word will be new to their audience), textbook dialogues that define all the words before you read the dialogue, textbook passages where they give you the word definitions in advance. Typically learner material designed to be used intensively is 90-94% words you know, and then it defines the key words you don't know. Typically learner material designed to be used intensively that uses less than 90% words you know feels exhausting, even if they define many key words, and that is why for example an Advanced Textbook excerpt feels exhausting if you're a Beginner - despite the Beginner and Advanced textbooks including some intensive reading. Any time you ever listened to a technical podcast, or read a technical text, and looked up a bunch of unknown words that seemed key to understanding the material, you were intensive reading.
Typically in our native language, we did a mix of intensive reading (teacher providing us vocabulary lists, textbook defining vocabulary) and extensive reading (the novels the library suggested were at our reading level, the reading material our teachers gave us that they did not expect us to need word-definitions to understand). Eventually, in our native language, we probably switched to reading and listening to most things extensively, and just looking up a key word once in a while if we hear a word we don't understand and feel particularly frustrated or confused because we can't understand it. The same eventually happens in the language you are learning - you'll look up a word occassionally, but you won't strictly need to. This could be called extensive listening/reading while looking up a few words, or intensive listening/reading while looking up a few words, as it's a bit of both. Different language learning materials will define the activity of "reading/listening while looking up only a few words" differently. I feel at the point you're understanding most stuff, whether you look up a word once in a while or not doesn't particularly change the primary activity which is just reading/listening for long stretches.
Immersion - used to define any activity where you are engaged with the language. Sometimes this is used to define a class that's entirely in the target language (example: a Spanish class taught entirely in Spanish, in Spain). Sometimes used to define living in a country that speaks the language (as in - you are immersed in the language any time you leave your home). Sometimes used to define staying at a home that speaks the language (immersed at home), or living with a partner/family members that only speak the language. Sometimes used to define watching shows, listening to, or reading media in the language - intensively or extensively. ALG Thai classes are an example of immersion classes, you take classes entirely in Thai, perhaps while living in Thailand. Dreaming Spanish website is an example of immersion classes, you hear only Spanish in the lessons. Watching anime in Japanese, whether you look up words or not (intensive or extensive), is immersing. Reading French books, whether looking up words or not (intensive or extensive), is immersing. Watching Chinese dramas, whether you look up words or not (intensive or extensive), is immersing. The term immersion can get confusing because, like the general term comprehensible input, it means A LOT of things broadly. When some people say immersion they mean engaging with the language extensively (no word lookups) - like Dreaming Spanish purist learners who are only learning by extensive listening. When other people say immersion they mean engaging with the language intensively (lots of word lookups) - like Refold Japanese learners who are looking up many words and making anki cards to study. Some people mean immersion as in they are living, working, doing everything in the language. Some people mean immersion as in they live in a country that speaks the language, but in their daily life they avoid using the language or engaging with it as much as possible. This is why it can be frustrating when you're told "just immerse!" okay but... what does the person saying that specifically think of when they say 'immerse' as there's many activities that count as immersion. And sometimes people mean wildly different things by it (such as meaning intensive versus extensive study, depending on the person saying to immerse).