[1] JST manufactures numerous series (families) and pitches (pin-to-pin distance) of connectors.
JST manufactures a large number of series (families) of connectors.
[2] The PCB (wire-to-board) connectors are available in top (vertical) or side (horizontal) entry, and through-hole or surface-mount.
A majority of JST through-hole headers can't withstand the temperatures required for reflow soldering, because the plastic has a lower melting point since they were designed for wave soldering methods.
Some JST surface-mount headers are designed to handle higher temperatures of reflow soldering.