Of course, the job description should specify education, previous job experience, certifications and technical skills required for the role. You may also include soft skills, like communication and problem solving, as well as personality traits that you envision for a successful hire. While you may be tempted to list out every requirement you envision for your ideal hire, including too many qualifications and skills could dissuade potential candidates.
A job specification could be considered a more precise job description that details the exact educational degrees, experience, skills, and requirements for a role. In most cases, these terms are used interchangeably and nearly always describe the same document.