You can create a single buffer to include all selected objects, or create individual buffers for each object. There are two ways you can buffer multiple objects at the same time. The first method is to create one buffer for all objects. Buffers are produced around each input object, and the resulting buffer objects are combined into a single output object.
The more powerful method is to create one buffer for each object. For example, you have a layer of satellite offices. You would like to create a five-mile radius buffer around every satellite office symbol. You select all office symbols (with the Select command), on the SPATIAL tab, in the Edit group, click Buffer, and select the option to create one buffer for each object. MapInfo Pro creates five mile buffer polygons around each point. With this method, MapInfo Pro considers the resulting buffers as individual region objects and does not combine them into one. Once you create a buffer region, you can search for objects within it, as with any other boundary.
About Buffer Calculations
Buffer functionality uses a Width setting to create a Buffer that is some measured distance from the outline of the object. Using Latitude/Longitude data, the perfect buffer width, as defined in native Latitude/Longitude decimal degrees, may change on different portions of an object. This is because the width is provided in some flat measurement unit, (for example, miles, meters), and the decimal degree to measurement transformation will vary depending on the location on the earth. For example, a mile spans a larger number of latitude degrees as you move toward the poles of the earth and away from the equator.
MapInfo Pro calculates a native decimal degree width (converting from the input measurement unit) for one location in the object, typically the center of the bounding box. Thus, the measured On Earth (Spherical) distance from the boundary of the original input object to the boundary of the new buffered object may vary slightly from node to node. On small objects the distance may be negligible. On objects that span a large distance, such as the United States, the distance variation may be measurable.
In MapInfo Pro, you can produce Cartesian calculated buffers. Using this option, the data is considered to be in a flat-projected coordinate system, and the measured buffer widths are calculated using Cartesian distances. This produces exact buffers (as measured by the Cartesian Distance functions) as long as the data in not in a Latitude/Longitude projection.