Transitions in design refer to the way that different elements or pages in a design move or change from one state to another. They can be used to create smooth, fluid experiences for users as they navigate through a website or app, and can help to improve the overall usability and aesthetic of the design.

There are many different types of transitions that designers can use in their work, including:

1. Fade transitions: This type of transition involves one element fading out while another element fades in, creating a smooth transition between the two.

2. Slide transitions: Slide transitions involve one element sliding off the screen while another element slides in to take its place. This can be used to create a sense of movement within a design.

3. Scale transitions: Scale transitions involve one element growing or shrinking in size as another element appears or disappears. This can be used to create a sense of depth and movement within a design.

4. Rotate transitions: Rotate transitions involve one element rotating or turning as another element appears or disappears. This can be used to create a sense of dynamism within a design.

5. Other types of transitions: There are many other types of transitions that designers can use, such as zoom, skew, and blur transitions.

In recent years, there has been a trend towards using more subtle and seamless transitions in design to create a smoother and more cohesive user experience. There has also been a trend towards using animations and microinteractions, which involve small, interactive elements that provide feedback to users, to enhance the overall user experience.