The most frequently used directives in Content Security Policy are:
default-src: specifies the default sources for all other directives.
script-src: specifies the sources from which scripts can come.
style-src: specifies the sources from which stylesheets can come.
img-src: specifies the sources from which they can come images.
connect-src: specifies the sources from which network requests can come.
font-src: specifies the sources from which fonts can come.