What is dot-style?

Answer 1

In keyboarding, DOT-STYLE is used in place of a hyphen when writing telephone numbers. In the United States, hyphens are used after the 3 digit area code and after the first 3 digits of the telephone number: example, 745-567-3478. Another format is used in many countries, is to replace the hyphens with periods: example, 745.567.3478.

Ref: Ober, Johnson, Zimmerly, Gregg College Keyboarding & Document Processing 10th edition, (2008)