In this paper I briefly compile the available information on 15 X-ray burst sources. In general, the bursts appear at more or less regular intervals of hours to tens of hours. These intervals can change by factors of ~ 2 or more. The total flux density of the bursts differs by 1–2 orders of magnitude from source to source. For some sources the total flux density of individual bursts can vary appreciably on a timescale of one burst interval, although in general, such changes are smaller than a factor ~ 2. Some burst sources (possibly all) have burst-active and burst-inactive periods. For some sources burst spectra ‘soften’ in time, for others they ‘harden’ and for one source both ‘softening’ and ‘hardening’ has been observed. Several (maybe all) burst sources permanently emit a ‘steady’ flux of X-rays. It is known only for a few sources how the burst activity is correlated with the ‘steady’ X-ray emission and how the total flux in individual bursts is related to the time interval between the bursts. Burst sources are distributed along the galactic equator; most of them are not located in globular clusters. There is insufficient evidence to assume that they are associated with super-massive black holes. It has been suggested that X-ray bursts are caused by plasma instabilities in accreting neutron stars (possibly in binary systems). However, no evidence exists to date that this is the case.