Yes, I mean 'determiners' by 'articles'. A/an is called 'indefinite article', while 'the' is called 'definite article'.
Articles can be so tricky to use, though. Sometimes you need to put an indefinite article before a noun or noun group, while sometimes you should use a definite article instead, or don't use anything, which is callled 'zero article'.
You say 'the Great Wall', 'the BBC', 'the University of London' but 'Hyde Park', 'CNN', 'Beijing University'. 'In prison' and 'in a prison' don't