John Dobson, a telescope maker, decided to make telescopes out of simple, readily available parts. This design idea has become popular for commercial visual telescopes. This telescope design is generally not usable in astrophotography.
DATE OF BIRTH - This abbreviation indicates that the date of birth for the associated individual is attached (if known). If only part of the date is known, that part is defined; if no part of the date is known, the data following this abbreviation is blank.