sed replace

sed -i 's/original/new/g' file.txt
sed -i 's/old-text/new-text/g' input.txtsed -i 's/foo/bar/g' hello.txtJust use one of following commands for replacing a number of:
sed "s/[0-9]//" f.txt	#One single digit as 1
sed "s/[0-9]\+//" f.txt #Further digits as 837, specifying match repetition "\+"
sed "s/[0-9]\+\.[0-9]\+]//" file.txt #Float type with decimals#on my mac
sed -i -e 's/old-text/new-text/g' text.txtFor using match in sed replacement, just border it with '\(' and '\)':
echo Before123 | sed 's/Before\([0-9]*\)/\1After/g'
123After	# number is matched withtin '\( \)' and replaced in '\1'
Example with 2 match replacements
echo a_b | sed 's/\(^.*\)_\(.*$\)/first is \1 and \2 is after/g'