These titles are not available at the UW Bothell campus library, but can be requested and sent here from other UW Libraries locations.
"PhD is short for Doctor of Philosophy (also abbreviated to DPhil or Dr.Philos). This is an academic or professional degree that, in most countries, qualifies the degree holder to teach their chosen subject at university level or to work in a specialized position in their chosen field." - Hasna Haidar, What is a PhD?
Whether or not one earns a master's before or during a PhD program is dependent on the school and field of study. The level of specification for application requirements to PhD programs increases beyond those of Master's programs. Conferring with the schools that have faculty members and specialize in the research area of your interest is an important first step in applying to a PhD program. Here are a few websites that share information about the pros and cons of PhD programs.
These links provide general information about preparing for applications to PhD programs.