Okay kiddo, Aldec is a company that makes computer software to help engineers test and verify their electronic designs. They help make sure that the electronics work properly before they are made into real-life products like phones, cars, or even planes.
It's kinda like when you play with Legos, you want to make sure all the pieces fit together correctly before you show it to your mom or dad. Aldec does this for electronics engineers by testing their designs to make sure everything fits properly and works correctly.
So basically, Aldec is like a big helper for engineers who make really cool things with electronics!