Slack, a collaboration hub that brings people together within organizations, strives to ensure that its products and people focus on making work life simpler, more pleasant, and more productive. This notion is best described as Slack's

mission statement

Explanation:

A company's mission statement defines the reason why the company exists; what is its business (what product or service they provide), its objectives (or goals) and how they will reach these objectives. It should also include who's needs they are satisfying (target market).