#### Continuous time Signal

**continuous-time signal** is a varying quantity (a signal) whose domain, which is often time, is a continuum (e.g., a connected interval of the reals). That is, the function’s domain is an uncountable set. The function itself need not to be continuous.

##### Properties

- The continuous-time signal is an analog representation of a natural signal.
- Continuous-time variable is denoted by letter t.
- The continuous-time signal can be I converted into discrete-time signal by the Euler’s method.
- The conversion of continuous to discrete time signal is comparatively easy than the conversion of discrete to continuous-time signals.
- The value of the signal can be obtained at any
**arbitrary point**of time. - It is defined over a
**finite or infinite domain**of sequence. - The continuous-time signals are not used for the
**processing of digital signals**.

#### Discrete time Signal

** D****iscrete-time signal** is a time series consisting of a sequence of quantities.

**Properties**

- The discrete-time signal is a digital representation of a continuous-time signal.
- Discrete-time variable is denoted by a letter
**n.** - Represented by
**x[n] = [1,2,3,4,5]** - The discrete -time signal can be converted into continuous-time signal by the methods of zero-order hold or first-order hold.
- The conversion of discrete to continuous time signals is very complicated and it is done through a sample and hold process.
- It is defined over a
**finite domain**of sequence. - The value of the signal can be obtained only at
**sampling instants of time.** - The discrete-time signals are used for the
**processing of digital signals.**

The District Time Signal is represented by

x[n] = {1,0,1,2,2,1}

↑

The upper arrow is used to show that the value of **n** is **zero(0)** at this point.