They are two type of data: numerical and categorical
numerical are divided into continuo and discrete
categorical are set of values and can be ordinal (containing order), binaries (yes/no, true/false, 0/1) and
It is different from text type, because: preserve order on plots, help on storage and indexing, possible values are enforced
The enforced can bring strange behavior if an unknown value appears. For R this value can receive NA but for python/pandas does not have a standard behavior.
Each row is known as sample for DS, but can be a record or observation as well
A sample can be a collection of rows for statistician