A sales manager is someone who is responsible for leading and guiding a team of sales people in an organization. They set sales goals & quotas, build a sales plan, analyze data, assign sales training and sales territories, mentor the members of his/her sales team and are involved in the hiring and firing process.
Sales executives are the key point of contact between an organisation and its clients: answering queries, offering advice and introducing new products. Their work includes: organising sales visits. demonstrating and presenting products. establishing new business.
Human resources are the people who make up the workforce of an organization, business sector, or economy. "Human capital" is sometimes used synonymously with "human resources", although human capital typically refers to a more narrow view (i.e., the knowledge the individuals embody and economic growth).