[logicalmonster]

1) Job titles can be pretty meaningless and are inconsistent throughout the profession. A senior or lead developer at an average non-tech company might barely qualify as a junior developer at a more technical firm. Some 26 year old who isn't very good might manage to get an inflated title simply by consistently job hopping every couple years.

2) If you had to give an objective definition of a senior developer, it might be somebody that can design and plan out complicated product features on their own and who others turn to for guidance. That doesn't mean that seniors don't sometimes need to collaborate with others, but generally they can figure out how to solve most of their own problems without having their hand held.