Definition
Software for managing a business's interactions with current and prospective customers — contacts, deals, communications history, pipeline. Examples: HubSpot, Salesforce, Pipedrive.
Why it matters
A CRM matters the moment a business has more leads and customers than one person can track in their head or a notebook — that's usually where follow-ups start getting missed and repeat customers get forgotten. It becomes the shared memory of the business, so anyone can see what was last said to a given customer. The common trap is buying a powerful CRM and never keeping it current; a half-filled CRM is often worse than a simple spreadsheet everyone actually uses.