# Set/Examples

## Examples of Sets

### Set of Living People

Let $P$ denote the set of living people.

Then:

 $\ds \text {The person reading this web page}$ $\in$ $\ds P$ $\ds \text {Julius Caesar}$ $\notin$ $\ds P$ $\ds -4$ $\notin$ $\ds P$

### Positive Integers Less than 10

The (strictly) positive integers less than $10$ form a set:

$\set {1, 2, 3, 4, 5, 6, 7, 8, 9}$

### People Called Smith

The collection of people whose surname is Smith form a set.