We have been in the house for 10 years, with carpet on main floor.
Surprisingly just found under the old carpet is hardwood floor! Removed all
the carpet, the hardwood is basically in good condition, don't think it
needs a refinish. But there are dozens of small nail holes scattered on the
floor (don't know why the previous owner made them). Also there will be
holes along the walls after I remove nail track strip.

How to repair the holes? just want to make them more invisible.

Thanks!