What YAML is
YAML uses indentation instead of brackets. It is a superset of JSON, supports comments, and is meant to be edited by hand.
Kubernetes manifests, CI pipelines, Ansible playbooks and most modern config files.
What R DataFrame is
R code that builds a data.frame from character vectors.
Statistics and R notebooks.
What changes when you convert YAML to R DataFrame
A YAML list of maps reads as rows and columns directly. Anchors and aliases are resolved before the table is built, so a repeated block arrives expanded rather than as a reference.
stringsAsFactors is set to FALSE explicitly. It has defaulted to FALSE since R 4.0, but being explicit means the snippet behaves the same on older installs.
What carries over from YAML to R DataFrame
One property of the YAML has no home in R data frame, and it is worth knowing which before you convert.
YAML can hold a value that is itself a list or an object. R data frame has only flat cells, so nested values are flattened into one cell rather than being spread across columns.
R data frame marks header cells differently from data cells, so the keys are lifted out and written once as a marked header row rather than repeated on every row.
Both formats record types, so numbers, booleans and nulls survive as themselves rather than as text.
The identifier 007 comes out of the R DataFrame as 007. Reading it as a number would have made it 7, and an id that changes value is worse than one that stays text.
The role "Analyst, data" survives with its comma, in one cell rather than split across two. That is the first thing to check in any converted table, and the usual place a R DataFrame file goes wrong.
The quotes around Jonah "Jo" Pryce are escaped with a backslash in the R DataFrame.