Energy is a property of matter that
Heat is easier to get than work. (If you don't believe this, just rub your hands and you'll convert work into heat. To do the reverse, you have to buy a special device that we call a heat engine.) Successful conversion of heat to work in a practical heat engine has brought about the industrial revolution in the nineteenth century.
We get radiation as a 'byproduct' (of nuclear energy utilization, in which the objective is to produce heat) or as Nature's gift (from the Sun); the latter is useful (for the most part), while the former can be very dangerous (we refer to it as radioactivity or radioactive waste). We also now know how to produce certain forms of radiation ourselves (e.g., TV, microwave and radio signals), and this has brought about the current communications revolution.
These are the energy forms that our industrial society needs, but they are not the ones that are readily available. Heat is available, but not where and when we need it. In summer, when it is plentiful, we want to get rid of it (using air conditioning). In winter, when it is scarce, we can't get enough of it (so we produce it in furnaces).
The following energy forms (referred to as the 'primitive' ones) are readily available to us on Earth:
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