What Right to Work Means
The U.S. right to work legal principle is sometimes confused with that of employment at will or it simply doesn't mean what some think it does. For example, it doesn't mean that all U.S. citizens are entitled to work if they wish. While that's generally true, it's not what right to work means in legalese.
In legalese, right to work more specifically means that otherwise-qualified employees are entitled to work at unionized workplaces, without joining the associated unions or paying regular union dues. But right to work (nonunion) employees might have to pay unions for the portion of dues spent representing them, such as pursuing grievances on their behalf.
Right to work employees who are part of a "bargaining unit" have the right to union representation, that is equal to those in the same bargaining unit who've joined the union. A bargaining unit is a group of employees who have similar work duties, share a workplace, and presumably have similar interests when it comes to pay, hours and other working conditions.
In other words, under the right to work principle, workers don't have to join unions or pay regular union dues to land or keep jobs. They may also cancel union membership at any time, without losing their jobs. But they are still entitled to fair and equal union representation while working in bargaining units of unionized workplaces. However, they might have to pay unions for the cost of such representation.