Please defined selector property and value in css

Answer 1

Css has selectors instead of tags and they are basically the tag names and are used to style particular elements. If you take the following example:

p {
    color: red;
    text-align: center;
}

P = Selector
Color and Text Align = Property
Red and Center = Value

Answer 2

The selector is
points to the HTML element you want to style.

Answer 3

p {
color:red; text-align:right;
}
for the question asked=
p= selector
text align=property
right=value

Answer 4

p{color:green;}
selector = p
property = color
value = green

Answer 5

Selector, basically, tells the browser which html element(s) need to be modified. And browser modifies it (them) by overvriting default values of some properties of that element (depends on the browser) with ones, specified in the stylesheet.