Everyone has at some point been in a car and imagined that they were actually sitting still and the world was moving around them. *  Turns out you were right.  And all the people watching you pass by: same thing.  It's diplomacy in action!
Each speed in each direction is a frame.
Two cars driving side by side are in the same frame.
The ground around them is in a different frame.
The sun above them is in yet another frame.

The only thing that determines a frame is its movement compared to other frames (one might say "relative" to other frames).
 
In Sacramento the city enforces the speed limit by timing their stop lights to turns green in succession.  Anyone moving to fast (left dashed line) will hit a red light, as will anyone moving too slow (right dashed line).  For those of you who enjoy thinking about menial things way too much, you'll realize that what the city is trying to do is encourage drivings to preferentially select a particular relativistic frame.
In this case about 35 mph with respect to the Earth's frame.

In the frame of the Earth (and Sacramento) the car is moving such that it always passes through green lights.  The X axis is position on the street.  The T axis is time.  In the city's frame each light is switching between red and green in time.



In the car's frame the city is moving underneath the tires at 35 mph.  Every light that passes by is green.

Both of these are pictures of the same street, over the same amount of time, from different frames.

You can also make events happen closer or farther apart by moving yourself.  For example: Two bombs go off in the same place (Earth frame), but at different times.  When the first one goes off you should change to a frame in which the second bomb explodes in a different place (run away).

Here's two events!  Could be anything!  Two parties!  Two rocks hitting the ground!  Your mom and two things she did!


Here's something that experiences both events!  It must be moving (according to you)!  It's going to the parties!  It's catching the rocks!  ......!


Here's the same thing from another perspective!  Everything happens in the same place!  The parties are at the same house!  The rocks land in the same place!  Your mom!