too broad a topic!!
the *.* is a variable
dir *.* lists the current directory
dir *.* /s lists the content of the current directory and the contents of all the sub directories in this case the /s is called a switch
dir /w lists all the files and folders in a directory but not the files in the subfolders
dir /w/p does the same as above except a page at a time
dir b ? ? ? ? ? ? ?.r?s seeks filenames beginning with b and the extension must begin with r , any middle letter and end with s
is this the sort of thing for which you are looking?