What the ones and zeros are
Each character becomes its numeric code in base 2. In ASCII that is one byte per character — A is 01000001, which is 65.
Beyond ASCII it is not one byte. UTF-8 uses two to four bytes for accented letters, CJK characters and emoji, so a single emoji becomes 32 binary digits. Converters that assume one byte per character produce nonsense for anything outside English.
Decoding binary you were sent
Groups of eight, separated by spaces, is the usual form. Spacing is tolerated here because people paste it inconsistently, but the total has to be a multiple of eight — a stray digit shifts every character after it.
Frequently asked questions
Why is one character more than eight digits?
Because it is not ASCII. UTF-8 uses two to four bytes for accented letters, CJK characters and emoji, so an emoji is 32 binary digits.
Does the spacing matter?
Not for reading — spacing is tolerated. But the total number of digits must be a multiple of eight, or everything after the stray digit decodes wrongly.
Is binary a way to hide text?
No. It is a different way of writing the same characters and anyone can convert it back instantly.
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