Having a smart home typically means you have set up your devices with a wireless protocol so that they run either with voice control, automatically, with routines or schedules, or with you controlling them remotely with a mobile device or computer. Automations are set when your devices react to a trigger without your involvement at the time it happens. This trigger can be an action from you or someone else, or a schedule, temperature or weather changes, motion, or a device status. Automations can be simple or intricate, you can set several devices to work together, like turning on the dehumidifier and a ceiling fan when the humidity reaches 70%, for example. So you can have a smart home without automations but it'd be hard to have automations without a smart home.