Use the tool below to hide your messages in plain text. In the box on the left, add your innocuous text. Then, on the right, add your secret message! The box will turn purple (and the Encode button will tell you your message is too long) if you need to either (A) increase the size of your left-side text, or (B) decrease the size of your secret text.
Once you've added your text to encode, hit the Encode button. If all has gone well, you should see your plaintext again... Exactly like it appeared before.
Your secret message has been injected into your plaintext where it cannot be seen. Copy and paste that text and save it someplace safe. Then, when you need to decode it, put it back in the same box (the first wide one) and hit Decode. Your secret message will (magically) reappear.
First, your message was converted to binary. This binary text was then interjected into your plaintext, using the typographical non-breaking-zero-width-space. Normally, this is used in typesetting for making sure that text doesn't 'wrap' at an undesired point (for instance, in the middle of a really long number). However, here, it's used to represent a binary 0. For every 1 we encounter, we put another letter of your plaintext. For every 0, we add a zero-width-non-breaking-space. Then, in order to decode this message we simply reverse the process.