s/regexp/replacement
If the search is successful, replace regexp with replacement.
sed ’s/oldword/newword/g’
Substitute newword for oldword. The g makes the substitution global otherwise only the first occurrence of oldword would be matched.
sed ’s/word/d’
Delete the entire line that contains word
sed ’s/word//’
Delete just the word word
sed -n ‘10,20p;20q’
Print lines 10-20
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