They are around 1 mm at length.
They are sucking the leaves fluids and scrubbing the leaves and fruits.
They can cause deformed fruits, specially to cucumber,
as a result of eating the flower’s pollen
And can also transfer several viruses, especially in tomato and pepper.
It is recommended to use at least 4 kinds of different pesticides,
and alternate between them every 3 days,
in order to overcome pest’s resistance, and completely exterminate them.
For further information about this, read this post , and this post also.
Best pesticides for thrips,