AKA business estate.
Land in the city is at a premium. While many businesses need to be highly visible and easily accessible, many do not. If you need to go to a doctor or the offices to your cable company, you are probably going to be willing to spend a little trouble hunting them down, and there are many companies that will rarely if ever need to have customers in their offices at all. For these companies, often the best location is a business park.
The definition of a business park is a bit vague. Towns of only a few thousand people will have the equivalent of a strip mall tucked off on a side road, filled with medical specialists and other businesses that don't need a highly visible storefront. Metropolitan areas may have urban or suburban developments of hundreds of acres built up like small towns to provide cheap commercial locations for hundreds of businesses, including headquarters for national corporations. All of these are called business parks.
Any area zoned for commercial use (and sometimes light industry) may be called a business park, but generally these parks have walk-up (one story) businesses, or in the bigger ones, comparatively low-standing buildings of only a few stories. Ample parking is provided. Businesses rent offices from the developer, who provides landscaping, utilities, and all the other functions generally provided by a landlord.
Business parks are generally seen (by those who bother to think of such things) as a bit of a kludge as far as urban development goes. They serve their purpose, and there is nothing particularly wrong with them, but they are are hardly an elegant solution. Their use of comparatively low demand land puts them in competition with 'real' parks and suburbs. They are generally somewhat inconvenient and often hard to locate. In urban areas a serviced office or 'executive suite' may be a better option for businesses, and in smaller towns it is rarely necessary to resort to business parks. But the lower rent offered by these establishments often proves irresistible.