Grab and Parse a chunkc of text

[sumncguy]

Can you explain what the sed command does exactly here?

searches for a line that starts with Switch

sed /^Switch/

through an empty line

sed /^Switch/,/^$/

do not delete the match / deletes everything but the match

sed /^Switch/,/^$/!d

from the log called xxx.log

sed /^Switch/,/^$/!d xxx.log

grep just counts start of lines

sed /^Switch/,/^$/!d xxx.log | grep -c "^"

Thanks
SUM