Usability testing is a critical part of the design process that helps ensure that a product or system is effective, efficient, and satisfactory to use. It involves testing the product with real users to see if it's user-friendly and intuitive. The goal is to identify any usability problems, collect qualitative and quantitative data, and determine the participants' satisfaction with the product.

There are several types of usability testing:

1. Formative Usability Testing: This is done during the development process to make changes and improvements in the design. It's typically more informal and involves small groups of users.

1. Summative Usability Testing: This is conducted at the end of the development process and is used to validate the usability of a final product. It's generally more formal and involves larger groups of users.

1. Remote Usability Testing: In this type, users participate from their own location, which can provide more natural and diverse responses. It can be either moderated (real-time interaction with the user) or unmoderated (user completes tasks on their own).

The process of usability testing typically follows these steps:

1. Plan: Define what you want to learn from the test, identify your target audience, and create a test plan.

1. Recruit: Find participants who match your target audience. This can be done through various methods, such as recruiting agencies, social media, or your own customer base.

1. Test: Conduct the test by having participants complete tasks while you observe their interactions with the product. This can be done in-person or remotely.

1. Analyze: Review and analyze the data collected during the test to identify usability issues and areas for improvement.

1. Report: Communicate the findings and recommendations to your team and stakeholders. The report should highlight key findings, provide actionable recommendations, and be easy to understand.