Adding characters at the start and end of each line in a file

What is the best way to add some characters at the start and end of each line? Can it be done using Vim, or some other way?

In vim, you can do

:%s/^\(.*\)$/"\1"/

• s/regex/replace/ is vim command for search n replace.
• % makes it apply throughout the file
• ^ and $ denotes start and end of the line respectively.
• (.*) captures everything in between. ( and ) needs to be escaped in vim regexes.
• \1 puts the captured content between two quotes.