All of the above, computers are used by scientists to analyze data, make models and communicate with other scientists.
The advent of computers has contributed greatly to the fields of science. They have allowed for the collection and recording of vast amounts of data. They allow scientists to store information indefinitely and review it easily.
Computers interact with science in several specific ways. The first one is dealing with collecting and processing data. This is how the "Colossus" (the first large scale computer) was used.
Computers are also used in the field of mathematics. Calculations are done that would take humans more than one lifespan to complete. The computation of the digits of Pi is a good example.
The Internet allows for almost instantaneous sharing of data across any distance. This allows for easier collaboration with colleagues anywhere in the world.
See Techwalla's How Are Computers Used in Science? for more info.