Suggest an editImprove this articleRefine the answer for “What is signal encoding?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**Signal encoding** is the process by which data bits (0 and 1) are converted into a physical signal suitable for transmission over a communication medium. **Key point:** encoding defines what 0 and 1 look like and how the receiver tells bits apart, while encryption is about protecting data, not transmitting a signal.Shown above the full answer for quick recall.Answer (EN)Image**Signal encoding** is the process by which **data bits (0 and 1)** are converted into a **physical signal** suitable for transmission over a communication medium. Put simply: signal encoding determines **exactly how 0 and 1 will look "in reality"**, as voltage, light, or a radio wave. --- ## Why signal encoding is needed Computers work with bits, but: - you cannot send an "abstract 0" over a cable - you cannot send an "abstract 1" through the air So bits need to be **encoded into a physical signal** that: - can be transmitted - can be received - can be told apart from interference --- ## What this looks like in practice ### In wired networks - 0 and 1 are encoded as **voltage levels** - or as a change in signal shape Example: - high level is 1 - low level is 0 --- ### In fiber optics - 1 means there is a light pulse - 0 means there is no light pulse (or the other way around, depending on the standard) --- ### In wireless networks Bits are encoded as changes in: - frequency - phase - radio wave amplitude --- ## What encoding actually determines Signal encoding defines: - what 0 looks like - what 1 looks like - how to tell bits apart from each other - how the receiver understands where a bit starts and ends This is a **key task of the physical layer**. --- ## Important point for interviews **Encoding ≠ encryption** - encoding is needed to transmit the signal - encryption is needed to protect the data The physical layer **encodes**, but does **not encrypt**. --- ## Simple analogy Morse code: - a dot and a dash are encoding - the actual meaning of the message is not here yet --- ## Briefly, for the interview > **Signal encoding** is the conversion of bits (0 and 1) into a physical signal of a specific form that can be transmitted over a cable or through the air.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.