There are many different types of AI tools. The some of ones that are best known to the general public are ChatGPT, Google Bard, DALL-E, Midjourney, etc. There are many more that exist and more tools that are created everyday.
ChatGPT and Google Bard are known as natural language processors or generative AI Natural Language Processors is defined as "the branch of computer science—and more specifically, the branch of artificial intelligence or AI—concerned with giving computers the ability to understand text and spoken words in much the same way human beings can." - IBM
DALL-E and Midjourney are image generators, which take images found on the internet and create something based on those images and a prompt entered into the tools.