The primary task of the Debrecen Heliophysical Observatory (DHO) has been the
most detailed, reliable, and precise documentation of the solar photospheric
activity since 1958. This long-term effort resulted in various solar catalogs
based on ground-based and space-borne observations. A series of sunspot
databases and on-line tools were compiled at DHO: the Debrecen
Photoheliographic Data (DPD, 1974--), the dataset based on the Michelson
Doppler Imager (MDI) of the Solar and Heliospheric Observatory (SOHO) called
SOHO/MDI--Debrecen Data (SDD, 1996--2010), and the dataset based on the
Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory (SDO)
called SDO/HMI--Debrecen Data (HMIDD, 2010--). User-friendly web-presentations
and on-line tools were developed to visualize and search data. As a last step
of compilation, the revised version of Greenwich Photoheliographic Results
(GPR, 1874--1976) catalog was converted to DPD format, and a homogeneous
sunspot database covering more than 140 years was created. The database of
images for the GPR era was completed with the full-disc drawings of the
Hungarian historical observatories \'Ogyalla and Kalocsa (1872--1919) and with
the polarity drawings of Mount Wilson Observatory. We describe the main
characteristics of the available data and on-line tools.Comment: 25 pages, 11 figures, accepted for publication in Solar Physic
