AND and BUT...
These are both simple conjunctions. Conjunctions are words that join one word or sentence with another.
"And" usage in a sentence is used in joining two sentences of similar grammatical statues. Positive for positive and negative for negative.
Examples:
• I went to the market(positive) AND bought oranges. (positive)....right
• I didn't go (negative) AND I didn't see him. (negative)....right
• I went (positive) AND I didn't see him (negative)....wrong
"But" on the other is used when one sentence is positive and the other is negative or vice versa.
Examples:
• The book was lost (negative) BUT it was later found(positive)....right
• I went to the market (positive) BUT didn't buy the oranges (negative).... right
• The car was stolen (negative) BUT it was not found (negative).... wrong