The Lesson
Continuous data can take any value (within a range). Continuous data can (often) be measured. Continuous data is a type of quantitative data. It is described in numbers.Dictionary Definition
The Oxford English Dictionary defines continuous as "having no breaks; connected, unbroken."Real Examples of Continuous Data

A person measures the heights of other people.
The people's heights are continuous data. People's heights are not restricted to certain values, like 5 feet 5 inches or 6 feet. People's heights can take any value (within a reasonable range).

A person measures the time it takes to complete a task.
Time is continuous data. Time is not restricted to certain values, like 5 minutes or 6 minutes. It can take any value.
Continuous Data and the Number Line
Continuous data can be shown on a number line.Continuous data can take any value along the number line, whether whole numbers or any in between. This is why continuous data is often measured. The lengths along a ruler, or the times around the edge of a clock are like number lines.