1.4. What’s a prompt? #

Prompts serve as the input queries that guide these models to generate a specific type of output. The function of a prompt varies slightly between these two kinds of generative models, but the core principle remains consistent: a prompt initiates the generation process and steers the model toward producing content that aligns with the user’s intention.

For large language models, prompts are typically text-based queries or statements. They can range from simple requests, such as “Tell me about the history of Rome,” to more complex or conditional queries, like “Write a persuasive essay arguing for renewable energy adoption.” The prompt is fed into the model, which then produces text that ideally satisfies the query, all while adhering to the grammar, tone, and context specified.

In the case of text-to-image models, prompts still serve as input queries, but the output is visual rather than textual. Here, the text-based prompts may include descriptions or features that the user wants to see in the generated image. For example, a prompt like “a serene beach at sunset” would guide the model to generate an image of a beach with qualities that could be described as serene and with lighting conditions consistent with a sunset.

Naturally, various models yield distinct outcomes, but prompts always shape the contours of the output—whether that output is a block of text or a visual image.