Captions, Labels & Bold Words

Special text features in books and articles help readers understand pictures and learn important words.

Reading is good — doing is better. Practice Captions, Labels & Bold Words as an interactive lesson.

Definition

Captions, labels, and bold words are text features — tools authors use to give readers extra help. A caption is a sentence near a photo or drawing that explains what is happening in the picture. A label is a word or short phrase that points to a part of a picture to name it. A bold word is a word printed in darker, thicker ink to show it is very important or has a special meaning.

Remember the rule

Ask 3 questions: WHO or WHAT does the picture show? (caption) WHAT are the parts called? (label) WHAT word is the author telling me is extra important? (bold word)

Key words

caption: A sentence near a picture that tells you what the picture shows
label: A word or short phrase with an arrow or line that points to part of a picture to name it
bold word: A word printed in thick, dark letters to show it is a key word
text feature: A special tool in a book — like a photo, caption, or bold word — that helps you understand the writing
glossary: A mini-dictionary at the back of a book that explains bold words
nonfiction: Writing about real things, people, and events — where captions, labels, and bold words are used most often
diagram: A drawing with labels that shows the parts of something
author: The person who wrote the book and chose which words to make bold

Worked examples

You see a photo of a frog sitting on a lily pad. Under the photo it says: 'A green frog rests on a lily pad in the pond.' What kind of text feature is this?

→ This is a caption. It is a full sentence that explains what is happening in the photo. · Captions are almost always found right under or right beside a picture.

You see a drawing of a butterfly. There are lines pointing to different parts, and the words 'wing,' 'antenna,' and 'body' are written next to the lines. What text feature is this?

→ These are labels. Each word names one part of the butterfly's body. · Labels use lines or arrows to connect the word to the exact part they are naming.

You are reading a book about bees. You see this sentence: 'Worker bees collect nectar to make honey. Nectar is the sweet liquid inside a flower.' The word nectar is printed in thick dark letters. What text feature is this?

→ Nectar is a bold word. The author made it bold because it is an important vocabulary word for this topic. · Look for that word in the glossary at the back of the book — it will probably be defined there too.

A page in a science book has a drawing of a plant. Lines point to the flower, the leaf, the stem, and the roots, with those words written next to each line. Is this a caption or labels?

→ These are labels. They name the parts of the plant using short words, not full sentences.

Under a picture of two kids planting seeds, the text reads: 'Maya and her brother plant sunflower seeds in the garden.' Is this a caption or a label?

→ This is a caption because it is a full sentence that describes the whole picture, not just one part.

You see the sentence: 'Reptiles are cold-blooded animals.' The words cold-blooded are in bold. What should you do next?

→ Stop and pay attention! Cold-blooded is a key word. Read the next sentences carefully — they will explain what cold-blooded means. You can also check the glossary. · When you spot a bold word, the author is giving you a signal that this word matters.

Common mistakes

Mixing up captions and labels — remember: a caption is a full sentence about the whole picture; a label is just a word or short phrase pointing to one part
Skipping over bold words — bold words are signals to slow down and pay extra attention, not words to skip
Forgetting to look at the picture a caption describes — always look at the photo AND read the caption together so each one helps the other make sense
Thinking bold words are bold just to look fancy — authors always bold a word for a reason, usually because it is a key vocabulary word
Not checking the glossary when a bold word is confusing — the glossary is there to help you understand those important words

FAQs

Where will I find captions in a book?

Look just below or right beside a photograph or drawing. The caption is almost always the sentence closest to the picture.

Can a label be a whole sentence?

No. Labels are short — usually just one word or two or three words. If it is a whole sentence, it is a caption, not a label.

Do all books have bold words?

Most nonfiction books do, but storybooks usually do not. Bold words are most common in books about real topics like animals, science, or history.

What if I do not know what a bold word means?

First, keep reading — the author often explains it in the very next sentence. Then try the glossary at the back of the book. That is exactly what the glossary is for!

Why do authors use these text features?

Authors use them to help you understand the topic better. A picture alone does not always tell you everything. A caption, label, or bold word gives you extra information.

Can one page have all three — a caption, labels, AND bold words?

Yes! A nonfiction page might have a diagram with labels, a caption under the diagram, and bold words in the paragraphs nearby. Each one does a different job to help you learn.

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