American political parties typically hold national conventions every four years
to nominate their presidential candidates and to adopt their
platforms. A party "platform" is a metaphor for the party's announced principles, and a "plank" is a metaphor for a specific platform statement that supports those principles.
In 1840, the Democratic National Convention published its first platform.
Republicans adopted a formal platform at their first National
Convention in 1856. Both parties continued to adopt platforms
at their quadrennial national conventions since, except for 2020.
In that year, the COVID pandemic prevented thems from holding national conventions and adopting national
platforms. The American Presidency Project at the University of California, Santa Barbara provides a convenient source
for all existing platforms by both parties.
I read through all the platforms to identify specific party planks, which were
segments that (a) had action implications, and (b) stated or clearly
the party's position on the issue.