Different countries do things in two different ways.

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  1. which side to drive on

    blue=left . red=right


    Amazingly, countries can't agree on which side of the road to ride or drive on.

    Most countries originally decided depending on what equipment they had.

    Countries deciding later usually decided depending on where they imported cars from.

    Most of the countries driving on the left are former British Commonwealth countries.

    Canada chose driving on the right because of the open borders with the United States.

    Some countries on pacific islands changed to left side driving because they buy Australian cars.

    Sweden switched from left side driving to right side driving in 1967 to match the countries around it.
     - For years Swedes drove on the right in cars with steering wheels on the right.

  2. long and short scale

    lime=long . violet=short
    aqua=both . orange=none


    Another thing countries don't agree on:

    The long scale has major names (-illion) at multiples of 1,000,000 (six zeros).

    The short scale has major names (-illion) at multiples of 1,000 (three zeros).

    The long scale has minor names (-illiard) at multiples of 1,000 between major names.

    Some countries don't use base-10 numbers.

    The US uses the short scale. The EU uses the long scale.

    Metric prefix and power of 10NumberLong Scale nameShort Scale name
    (none) 10^01(none)(none)
    kilo 10^31,000ThousandThousand
    mega 10^61,000,000MillionMillion
    giga 10^91,000,000,000MilliardBillion
    tera 10^121,000,000,000,000BillionTrillion
    peta 10^151,000,000,000,000,000BilliardQuadrillion
    exa 10^181,000,000,000,000,000,000TrillionQuintillion

    When a worldwide news story is published, people have to try to figure out which scale the story uses.

    Except that some people don't know there are two scales. Some Europeans think the US budget is in exabucks.

    Too many reporters abbreviate number names to first letters. They should use metric prefixes instead.

  3. countries changing clocks twice a year

    blue=north summer
    orange=south summer
    light gray=stopped DST
    dark gray = never had DST


    Unfortunately Daylight-saving time was invented by Benjamin Franklin in 1874.
    At the time he was joking about to Parisians turning clocks forward an hour to save candle wax.

    DST was pretty much forgotten until World War I, when Congress required it to save fuel and electricity.

    After World War I, DST was removed until World War II, when it was again required.

    After World War II, several states decided to keep using DST. Other countries also adopted it.

    Note that the seasons are reversed in the southern hemisphere. This means:
     - The southern hemisphere summer is during the northern hemisphere winter.
     - Southern hemisphere daylight-saving time is during the southern hemisphere summer.

    Daylight-saving time is useless in the Torrid Zone (near the equator).

    Many countries adopted DST as a fad, and then got rid of its nuisance later.

    After air conditioning came into use, DST could no longer save energy.

  4. metric or others

    lime=US system . blue=metric
    violet=mixed metric and imperial
    red and orange=none of the above


    Before the Metric system, most measurements were designed to be handy in the use they were put to.

    The metric system was to be an unchanging set of measures based on physical constants that never change.

    The problem with the Metric system is that none of the standard Metric measures is handy.
     - Those using the Metric system are always using calculators to get the measures they need.
     - Recipes and building specifications often have 3-digit decimal numbers to show amounts.

    Users of the US system often use integer values of the measures to get what they need for a project.
     - Lengths needed are often exact multiples of the inch, foot, yard, teaspoon, or cup.

    Nobody has yet perfected a metric-sized egg.

    They had to make new Metric standards when the original values were found to be in error.

    Scientists pushed for all countries to adopt the Metric system, even though it made measurement more work.

  5. communism vs capitalism

    green=capitalist . red=communist
    yellow=mix . black=dictator


    The world is divided into two main economic systems:
     - Capitalism, which is based on doing work to make money.
     - Communism, which is based on making everyone equal.
     - A third case is a dictator controlling everything.

    There are varying levels of strength of each system.

    Some countries try to combine the two systems.

    Businesses and the people own the wealth in Capitalism.

    Government owns all of the wealth and businesses in Communism.

    Many countries waver back and forth depending on who is in power.

    Capitalist countries usually have bigger economies, while communist countries don't try for that.

  6. auto or demo crat

    blues=democracy . reds=autocracy


    The world is divided into two main ruling systems:
     - Democracies are based on the people voting for the leaders.
     - Stronger democracies let the people elect more leaders.
     - Autocracies are based on leaders picked by heredity or a ruling council.
     - Stronger autocracies let the people have less control.

    Some officials (e.g. judges) should not be elected because election would chose biased officials.
     - Judges should be chosen for their impartiality.

    There are two kinds of democracies:
     - Parliamentary democracy has the legislature picking the executives.
     - Presidential democracy has the executives elected separately.

    Both kinds of government can ruin anything.

  7. hemispheres

    orange=north . blue=south


    The world is divided into the northern and southern hemispheres.

    These things are different in the two hemispheres:
     - The seasons in the year are different in the two hemispheres:

    NorthernMAR-JUNJUN-SEP SEP-DECDEC-MARAnticlockwise

     - Bad weather storms, tornadoes, and hurricanes rotate in opposite directions.
     - Daylight-saving time (if used) is in different months (always excludes winter, see above).

    Stupid comments people who don't understand the differences in the seasons make:
     - All countries in the world should switch to Daylight-Saving Time on the same date.
     - How can it be hot in Australia now? The whole world is colder in January.

  8. day and nighr

    white=day . blue=night


    The world is divided into two hemispheres that constantly change:
     - The DAY hemisphere is the half of the earth the sun is shining on now.
     - The NIGHT hemisphere is the half of the earth the sun is NOT shining on now.

    The day and night zones and their edges move to the west on the map as the earth rotates.
     - This is why we have time zones.
     - The edge where day is to the east of night is the sunrise.
     - The edge where day is to the west of night is the sunset.
     - The edges are straight like on this Mercator map only at the vernal and autumnal equinoxes.
      - On other dates, the edges curve because the sun stays up at one pole and down at the other.
      - There are no daily light and dark cycles at the poles.
      - The sun circles the polar horizon once each day when it is up.

    Stupid comments from people who don't know that day and night are on different parts of the world at the same time:
     - The whole world should be in the same time zone.
     - It's night in the whole world at the same time.
     - How can it be dark where you are? The sun is up. I see it.
     - Santa Claus is stuck in New York City at 8 PM on Christmas Eve.
      - He must get home by midnight to deliver presents (movie plot).
        (Santa has already missed 15 hours of delivery time at 8 PM EST on Dec 24.)