Time

You know it seems like humans can't avoid the idea of time.

It's something they experience,

and they know that the world around them seems to change in time,

moment to moment,

and that in a way they feel that change within themselves.

And even if different people feel that change in different ways,

they can agree on how long the sun and the moon

take to go through their changes.

So they use the sun and moon for months and years,

and muslims mark different months of the year

with the fasting of Ramadhan

and the pilgrimage of Hajj.

And people found ways of marking the sun's travel across the sky using sundials,

and made water clocks and candle clocks for when they couldn't see the sun,

and had watchmen to call out the time at night.

And for muslims there are prayer times

marking out the clock of days.

And as people found that they could make better clocks than candles,

they divided the hours into minutes,

sixty in every hour,

and eventually, when they found a way to measure them,

they could even divide those minutes into sixty seconds.

And people are still using those units of time

all around the world today.

And they display time

in two forms,

analogue and digital.

Digital just gives you the number of each hour and minute, and even seconds,

with the number changing when that length of time has passed.

Analogue is what you see in the kind of clock with hands that move around a circle

without stopping,

when time is seen as in constant motion,

never actually at one point,

but always somewhere between one point and the next.

In days when time wasn't measured by the minute,

analogue clocks made time something much more vague.

They often only have four numbers, at the points of the compass,

3 6 9 and 12.

It might be that quarter to or quarter past or half past the hour

was close enough,

or almost or just after.

Clocks with hands and faces have been used for hundreds of years,

in fact many still use the old fashioned numbers

that they used 2000 years ago,

Roman Numerals.

Because they didn't have the Arabic Numerals that are used nowadays

they used letters for their numbers,

and because they didn't use zero or decimal placing

their maths was difficult and hard work.

The Romans used different letters for one and five

and ten and fifty and a hundred and a thousand,

the capital letters I V X L C M,

then put smaller numbers on either side of larger ones

with those on the left to be taken away from the larger number

and those on the right to be added to it.

So 3 6 9 12 reads as III VI IX XII.

And it's not just clocks where you can see Roman Numerals,

they can often be seen as a traditional way of writing the year something was made,

such as in the credits of films

or on the copyright page of books.

Sometimes fractions of seconds are important to know,

and sometimes knowing the year is good enough,