Fetching resources over the network is both slow and expensive: the download may require multiple roundtrips between the client and server, which delays processing and may block rendering of page content, and also incurs data costs for the visitor. All server responses should specify a caching policy to help the client determine if and when it can reuse a previously fetched response. — PageSpeed Insights
You can leverage browser caching like this:
# Enable browser caching
ExpiresActive On
# Set the default caching duration
ExpiresDefault "access plus 1 week"
# Change the caching duration by file type
ExpiresByType text/html "access plus 2 weeks"