In many science fiction shows and movies there are force fields that are invisible and can be turned on and off with the push of a button. How might the force fields of science fiction shows and movies work and what might they be made from?
There is some research on the subject of generating small magnetic fields that mimic the Earth's magnetosphere, in order to protect spacecrafts (and the people inside them) from dangerous radiation. Likewise, such a magnetic field would offer some defense against plasma weapons or particle beams. However, they would not offer defense against kinetic weapons or lasers.
If your setting has 'programmable matter' or nanobot swarms which respond to remote control, it might allow you to turn them into a protective sphere. That's really more of a shapeshifting matter shield than a true force field, though.