R has functions to generate a random number from many standard distribution like uniform distribution, binomial distribution, normal distribution etc.

The full list of standard distributions available can be seen using `?distribution`

. Functions that
generate random deviates start with the letter `r`

.

For example, `runif()`

generates random numbers from a uniform distribution and `rnorm()`

generates from a normal distribution.

## From Uniform Distribution

Random numbers from a normal distribution can be generated using `runif()`

function.

We need to specify how many numbers we want to generate.

Additionally we can specify the range of the uniform distribution using `max`

and `min`

argument.

If not provided, the default range is between `0`

and `1`

.

### Example: Uniform Distribution

```
> runif(1) # generates 1 random number
[1] 0.3984754
> runif(3) # generates 3 random number
[1] 0.8090284 0.1797232 0.6803607
> runif(3, min=5, max=10) # define the range between 5 and 10
[1] 7.099781 8.355461 5.173133
```

In the program above, we can also generate given number of random numbers between a range.

## From Normal Distribution

Random numbers from a normal distribution can be generated using `rnorm()`

function.

We need to specify the number of samples to be generated.

We can also specify the mean and standard deviation of the distribution.

If not provided, the distribution defaults to `0`

mean and `1`

standard deviation.

### Example: Normal Distribution

```
> rnorm(1) # generates 1 random number
[1] 1.072712
> rnorm(3) # generates 3 random number
[1] -1.1383656 0.2016713 -0.4602043
> rnorm(3, mean=10, sd=2) # provide our own mean and standard deviation
[1] 9.856933 9.024286 10.822507
```

In the program above, we can also generate given number of random numbers between a range.