A parent-friendly glossary of reading instruction jargon, from phonemic awareness to decodable texts, with notes on how each term helps you judge materials before you buy.
Quick takeaways
- Phonemic awareness works with the sounds of spoken language only; phonics connects those sounds to written letters. The two terms are not interchangeable.
- Decodable books let children practice the exact letter-sound patterns they have been taught, while leveled and predictable texts rely on labels, patterns and prediction.
- The science of reading is a body of research on how the brain learns to read, not a curriculum, product or brand.
- Research cited by science of reading initiatives indicates about 95 percent of students can learn to read proficiently with instruction based on that research.
- Compare materials by the skills they name and the order they teach them, not by level labels or marketing phrases.
Reading apps, book sets and tutoring programs all describe themselves with the same short list of jargon: phonemic awareness, decodable texts, structured literacy, high-frequency words. Publishers assume you already know what these mean, and few of them explain. That is a problem when the terms describe real differences in how materials teach, so this glossary defines the words you are most likely to meet and explains why they matter when you compare one program against another.
Phonemic Awareness vs. Phonics
These two terms sound interchangeable and are not.
Phonological awareness is the broad ability to notice and work with the sounds of spoken language, including rhymes, syllables and the beginnings and endings of words.
Phonemic awareness is the ability to hear, identify and work with the smallest units of sound in spoken words, with no print involved. A child doing phonemic awareness work might say the sounds in “mop” out loud or swap the first sound to make “top”.
Phonics is where print enters. It teaches children which letters and letter combinations stand for which sounds, so they can move from hearing sounds to reading and writing them.
Classrooms that follow the science of reading tend to use these terms often, along with “simple view of reading”, so hearing them from a teacher or seeing them in an app description is a sign the material draws on that research. Learning to read is a cognitive skill that has to be taught. Unlike talking, it does not develop on its own from exposure to good books alone. If you want to see how these skills build on each other over time, our timeline for learning to read at home lays out the sequence.
Blending, Segmenting and Other Skill Names
Programs often list these skills in their skill trackers and progress reports.
Blending means pushing individual sounds together to read a whole word, as in joining /c/, /a/ and /t/ into “cat”. It is the skill behind sounding out.
Segmenting works in the other direction: taking a spoken word apart into its sounds, which is what children do when they spell a word sound by sound.
Decoding is using letter-sound knowledge to figure out a written word on the page.
Encoding is the reverse process, spelling. A child who reads “flat” is decoding it; a child who writes it after hearing it is encoding it.
When an app says it “covers blending and segmenting”, that tells you it practices both directions of the sound-to-print connection, which most explicit reading programs treat as a core skill pair.
Decodable, Leveled and Predictable Texts
Three kinds of early books dominate the shelves, and they are built on different ideas about how children read.
Decodable books use words children can sound out based on their current reading skills and instruction. They give early and struggling readers repeated practice with specific spelling patterns, and they are usually sold in sets, with each book or group of books focusing on one letter-to-sound skill before introducing harder words and patterns. Because the sets move from simple words to more complex ones, parents and teachers can match a book to the exact skills a child has already been taught.
Leveled readers are books sorted into levels, but the labels generally rest on non-scientific measures such as the number of words per sentence, the theme of the book or a grade-level designation, not on which letter-sound patterns appear in the text.
Predictable texts are books built on repeated sentence patterns, where children often work out the words from the pattern and the pictures rather than by sounding them out.
The practical difference shows up in what a child does when stuck. With a decodable book, the fix is to sound out the word using skills already taught. With a leveled or predictable book, the child may guess, which can look like reading while skipping the practice that builds it.
Helpful tip
Ask your child’s teacher which reading skills have already been taught and which ones are being worked on this week, then pick decodable books that match. A book matched to taught skills gives practice; a book that does not match asks the child to guess.
Sight Words and High-Frequency Words
High-frequency words are the words that show up constantly in English text, words such as “the”, “and”, “said” and “was”. Programs track them because knowing them speeds up the reading of almost any sentence.
Sight words are words a reader recognizes instantly, without needing to sound them out. Any word can become a sight word once a child has read it enough times, and instruction often aims to make the most common high-frequency words instantly recognizable.
You will see the two labels used loosely, sometimes for the same list. When comparing materials, what matters is whether the program explains how it teaches those words, through letter-sound work where possible and careful practice where not.
Fluency, Vocabulary and Comprehension
Federal reading research groups five areas together as the pillars of early literacy: phonemic awareness, phonics, fluency, vocabulary and comprehension. The first two cover the sound and print skills above; the last three carry reading into real understanding.
Fluency is reading connected text smoothly, at a reasonable pace and with attention to meaning, rather than one halting sound at a time.
Vocabulary is the collection of words a child understands in spoken and written language. A child who does not know a word will struggle to comprehend a sentence built around it, no matter how well they decode it.
Comprehension is understanding and thinking about what was read. It is the point of everything else; decoding without comprehension is just pronunciation.
When a program claims to cover “all five pillars”, check that it actually describes work in each area rather than using the phrase as decoration.
You do not have to spend much to act on this vocabulary. Libraries lend early readers, and our roundup of free learning resources for families points to no-cost materials you can try before buying anything.
Structured Literacy and the Science of Reading
The science of reading is not a curriculum, product or philosophy. The phrase refers to decades of research into how the human brain learns to read. That research shows reading has to be actively taught, because written language is far newer than spoken language and humans did not develop an instinct for it. It also shows what is possible: research cited by science of reading initiatives indicates that about 95 percent of students can learn to read proficiently when taught with instruction based on that research, and lawmakers in 40 states and the District of Columbia have passed laws or implemented policies related to evidence-based reading instruction.
Structured literacy is the teaching approach most closely tied to that research. It teaches letter-sound relationships explicitly and in a planned sequence, one new pattern at a time, with plenty of review of earlier skills. Decodable books are designed to go along with a structured literacy approach, which is why the two terms often appear together.
Explicit instruction means the teacher demonstrates a skill directly instead of leaving children to figure it out from exposure. Systematic instruction means skills are taught in a deliberate order, from simpler to more complex.
The simple view of reading is a model that describes reading comprehension as the combination of word recognition and understanding of spoken language. If either side is weak, comprehension suffers, which is why a struggling reader may need work on sounds, on vocabulary, or on both.
Using These Terms to Compare Materials
Once you know the vocabulary, marketing claims get easier to test. The table below sums up the three text types so you can see the differences at a glance.
| Text type | How it is organized | What the child practices |
|---|---|---|
| Decodable | One new letter-sound skill per set, matched to instruction | Sounding out words with taught patterns |
| Leveled | A level label based on sentence length, theme or grade | Reading with support from cues and labels |
| Predictable | Repeated sentence patterns with picture support | Pattern recognition and prediction |
A few habits make comparisons sharper:
- Look for named skills, not named levels. A program that says “covers short vowels, then consonant digraphs, in that order” gives you something to check against what your child has been taught. A program that says “level C books” does not.
- Ask whether the sequence is explicit and systematic. Those words should come with a description of the order skills are taught, not just a promise that the program is “research-based”.
- Match practice books to taught skills. Decodable books work best when they line up with what your child is learning that week, so ask the teacher which skills have been covered and which are coming next, and whether they can recommend decodables for home practice.
- Be wary of programs that promise outcomes. Materials can be described by what they teach; no publisher can promise where your child will land.
If your child gets plenty of the right kind of practice and still struggles, the terms here become even more useful, because structured literacy instruction is often what specialists point to for readers with dyslexia. Our article on how much a dyslexia evaluation costs explains the evaluation process and what families typically pay, so you know what to expect before pursuing one.
Start small: pick one material your child already uses, find its skill list or level labels, and check each term you just learned against what it actually says.
Parents and students ask
What is the difference between phonics and phonemic awareness?
Phonemic awareness is working with the sounds of spoken language without any print involved. Phonics connects those sounds to written letters so children can read and spell words.
How do I know if a book is decodable?
Decodable books are usually sold in sets, and each set focuses on a specific letter-to-sound skill. Ask your child’s teacher which skills have been taught, then check that the book gives practice with those same patterns.
Is the science of reading a program I can buy?
No. It is a body of research about how the brain learns to read. Materials described as aligned to it should teach letter-sound skills explicitly and in a planned sequence.
Do sight words and high-frequency words mean the same thing?
They overlap. High-frequency words are the words that appear most often in text, while sight words are any words a reader recognizes instantly, which is often the goal for those common words.
This guide is general information for families. Follow your school’s policies, and talk to your child’s teacher, school counselor or pediatrician about your child’s specific needs.