The science of reading is built on the Simple View of Reading and emphasizes the five components of reading, plus oral language.

(Gough & Tunmer, 1986)
This model developed by Gough and Tunmer organizes the skills needed to become a proficient and successful reader into two categories: word recognition and language comprehension. The Simple View of Reading is a basic formula for reading comprehension. It says this: reading comprehension is the product of word recognition skills and language comprehension skills. We need both variables in the equation for students to become skilled, proficient readers. Students need efficient word recognition or decoding skills where they are accurately and automatically reading the words on the page without the aid of context clues or pictures*. They also need fully developed language comprehension skills, which references the ability to understand language. In order for a student to understand text, they need to decode the words on the page and then make meaning of the words, sentences, and overall text.
*Use of context clues and pictures is an acceptable comprehension strategy. The use of context in comprehension refers to something quite different from the use of context in word recognition. Examples of using context to aid in comprehension are determining the meaning of unknown words, understanding words with multiple meanings, and understanding pronoun referents. The use of context to aid comprehension should be consistently encouraged by teachers, although some contexts are more helpful than others for this purpose.
The skills needed to become a proficient reader can also be seen in the Reading Rope model. (Scarborough, 2001) This model aligns with The Simple View of Reading but gives us a little more information on the skills that are required in each variable of the equation.
The top portion of the rope detail the skills needed in the language comprehension category shown here in red. These skills are background knowledge, vocabulary, language structures, verbal reasoning, and literacy knowledge. The word recognition or word reading skills are phonological awareness, decoding, and sight recognition.
As the language comprehension skills become strategic and word recognition skills become automatic, a student becomes a skilled reader. This means their reading is fluent and their language skills are adequate so that the reader isn’t having to focus their mental energy on either the language comprehension pieces or the word recognition pieces and they are able to focus on comprehending, taking in and understanding what they are reading.
♦♦Follow-up question: Why is phonics often focused on in conversations about the science of reading?
Students need to develop both word recognition and language comprehension skill sets to become successful and proficient readers. Minimal phonics instruction or teaching concepts incidentally as they come up in text is not enough instruction for most students. Phonics is often the focus of conversation around research-based practice because it is the weakest component of many programs which do not align with the science. All students learn best through explicit and systematic instruction which teaches students phonics concepts in a structured sequence where lessons are building upon one another. Additionally, there is not as much debate on how to teach vocabulary and comprehension, so this side of the equation is not as thoroughly discussed but is equally important in instruction and student reading. Quality instruction in all components of reading is essential for effective instruction. See the Selecting Scientifically and Evidence-Based Instructional Programs page for more information on criteria for effective instruction in all components of reading.
(Schwartz, 2019)