It's very simple:
/tp @p ~ ~2 ~
teleports you two blocks in the air
/tp @p 100 64 13
teleports you to a coordinate.
the Video shows you how it works.
If you have exact coordinates, even if you throw something on the pressureplate it teloports you there.
If you have ~ relative, it just teleports you the amount of relative towards the direction
this also works with entities: @e[type=Creeper]
will teleport all creepers or
@e[type=Creeper,c=1]
teleports one creeper
also @p[lm=15]
only teleports players under level 15
and @p[l=15] only teleports over 15
same works with range: @p[r=5] and count: @p[c=1] So the final command is:
/tp @p[c=1,r=5,l=15,lm=16] ~ ~10 ~ 
this teleports the nearest player in range of five which is level 15 or 16 10 blocks higher.
If I forgot something or there is anything else you need to know about /tp or other commands, leave a comment below. Thanks :)