Note that each variable name is surrounded in tick marks ( ```` ) - sorry, what do you mean by this?

Note that each variable name is surrounded in tick marks ( ```` ). This is because the titles contain spaces, which are not valid in R variable names. When you work with tidyverse functions, surrounding invalid R variable names with tick marks will allow R to interpret them properly.

Sorry, I can’t understand what do you mean by this?

And how enrich your R data analysis path comparing with python?

Hossain,
The tick marks are used to enclose variable names which have spaces so that the variables can be used with the tidyverse functions. As I hope you know, valid variable names in R cannot contain spaces. For example, whilst major_category is a valid variable, major category is not. However, surrounding major category in tick marks makes R interpret it as a valid variable.

See the following link for sample code: https://app.dataquest.io/m/323/data-cleaning-with-r/3/sat-data-changing-data-types-and-creating-new-variables