Different Kinds of Information

The boxes (variables) you just met can hold different kinds of things. Just like in real life you'd treat a jar of coins differently from a stack of letters, a computer treats different kinds of information differently.

Three friendly types to start with

You'll meet many types eventually, but here are the three most common, in plain terms:

• Text — words and sentences, like a name or a message. Programmers often call this a string (think of letters strung together like beads). We usually wrap text in quotes: "Hello".
• Numbers — like 7, 100, or 3.5. No quotes needed. You can do math with these.
• True/False — a yes-or-no value, like "is the door locked?" Programmers call this a boolean. It can only be true or false.

Why the difference matters

The type changes what you can do. Look closely at these two lines:

5 + 3
"5" + "3"

The first uses numbers, so the computer does math: the result is 8.

The second uses text (note the quotes!), so the computer sticks the characters together: the result is "53". Same-looking symbols, completely different meaning — all because of the type.

You don't need to memorize this

You won't be tested on a long list of types. For now, just remember the big idea: information comes in different types, and the type affects what the computer can do with it. That awareness alone will save you headaches later.