Critical thinking is a key skill in any walk of life, especially for students at all levels of study, whether basic or advanced. Simply put, critical thinking is the ability to think clearly and rationally, understanding the logical connection between ideas.
This way of thinking encourages students to be active participants in the learning process instead of passive recipients of information. Those who engage in critical thinking don't simply allow their brains to be crammed with information; they actually think about what they've been taught and actively question and evaluate the ideas that have been transmitted to them.
Armed with critical thinking skills, it becomes possible for students to engage in problem solving, which is itself a very important life skill. Even those of us not currently engaged in formal education need to solve problems in our lives on a regular basis. Critical thinking makes it a lot easier for us to do this, as it gives us the ability to see our problems from a more objective standpoint. If we're too caught up in our subjectivity, too emotional about dealing with our problems, then it's all too easy to lose perspective, and invariably, the consequences are negative.
In an age of fake news and with the internet positively infested with all kinds of disinformation, critical thinking skills are more important than ever. People need them in order to be able to sort the wheat from the chaff, as it were: to know which pieces of information we're presented with are true and which aren't. Only then will we be in a position to hold reasoned, informed opinions about the subjects that concern us.