diff --git a/css-easing-1/Overview.bs b/css-easing-1/Overview.bs
index a196ea3d5bf..76eba3bde5f 100644
--- a/css-easing-1/Overview.bs
+++ b/css-easing-1/Overview.bs
@@ -125,16 +125,126 @@ The syntax for specifying an [=easing function=] is as follows:
   <<step-easing-function>></div>
 
 
-<h3 id=the-linear-easing-function oldids=linear-timing-function-section>The linear easing function: ''linear''</h3>
+<h3 id=the-linear-easing-function oldids=linear-timing-function-section>The linear easing function: ''linear()''</h3>
 
-The <dfn export lt="linear easing function|linear timing function">linear easing
-function</dfn> is an identity function
-meaning that its [=output progress value=] is equal to the
-[=input progress value=] for all inputs.
+A <dfn export lt="linear easing function|linear timing function">linear easing function</dfn>
+is an easing function
+that interpolates linearly
+between its [=linear easing function/points=].
 
-The syntax for the [=linear easing function=] is simply the
-<dfn dfn-type=value for=easing-function>linear</dfn> keyword.
+A [=linear easing function=] has <dfn for="linear easing function">points</dfn>,
+a [=/list=] of [=linear easing points=].
+Initially a new empty [=/list=].
 
+A <dfn>linear easing point</dfn>
+is a [=/struct=]
+that has:
+
+<dl dfn-for="linear easing point">
+
+: <dfn>input</dfn>
+:: A number or null
+
+      Note: The [=linear easing point/input=] is only null during the [=create a linear easing function=] algorithm.
+
+: <dfn>output</dfn>
+:: A number
+
+
+</dl>
+
+<section algorithm="to calculate linear output progress">
+
+To <dfn export>calculate linear output progress</dfn>
+for a given [=linear easing function=] |linearEasingFunction|,
+and an [=input progress value=] |inputProgress|,
+perform the following.
+It returns an [=output progress value=].
+
+1.   If |linearEasingFunction|'s [=linear easing function/points=] [=list/is empty=],
+     then return |inputProgress|.
+
+1.   If |linearEasingFunction|'s [=linear easing function/points=] [=list/size=] is 1,
+     then return |linearEasingFunction|'s [=linear easing function/points=][0]'s [=linear easing point/output=].
+
+1.   Plot |linearEasingFunction|'s [=linear easing function/points=] points on a graph
+     using [=linear easing point/input=] as the x-axis
+     and [=linear easing point/output=] as the y-axis.
+
+1.   Interpolate the points linearly.
+
+1.   Extend the ends of the graph to infinity using the final angle of the line at either end.
+     If the line starts/ends with two points of the same position, the line should extend along the x-axis.
+
+1.   Return the y-axis value corresponding to the x-axis value of |inputProgress|.
+
+</section>
+
+<dfn function lt="linear()">linear(<<linear-stop-list>>)</dfn>
+
+<pre class="prod">
+  <dfn>&lt;linear-stop-list></dfn> = [ <<linear-stop>> ]#
+  <dfn>&lt;linear-stop></dfn> = <<number>> && <<linear-stop-length>>?
+  <dfn>&lt;linear-stop-length></dfn> = <<percentage>>{1,2}
+</pre>
+
+<section algorithm="to create a linear easing function">
+
+To <dfn>create a linear easing function</dfn>
+from a <<linear-stop-list>> |stopList|,
+perform the following.
+It returns a [=linear easing function=].
+
+1.   Let |function| be a new [=linear easing function=].
+
+1.   Let |largestInput| be negative infinity.
+
+1.   For each |stop| in |stopList|:
+
+     1.   Let |point| be a new [=linear easing point=].
+
+     1.   [=list/Append=] |point| to |function|'s [=linear easing function/points=].
+
+     1.   Set |point|'s [=linear easing point/output=] to |stop|'s <<number>>.
+
+     1.   If |stop| has a <<linear-stop-length>>, then:
+
+          1.   Set |point|'s [=linear easing point/input=] to whichever is greater:
+               |stop|'s <<linear-stop-length>>'s first <<percentage>> as a number,
+               or |largestInput|.
+
+          1.   Set |largestInput| to |point|'s [=linear easing point/input=].
+
+          1.   If |stop|'s <<linear-stop-length>> has a second <<percentage>>, then:
+
+               1.   Let |extraPoint| be a new [=linear easing point=].
+
+               1.   [=list/Append=] |extraPoint| to |function|'s [=linear easing function/points=].
+
+               1.   Set |extraPoint|'s [=linear easing point/output=] to |stop|'s <<number>>.
+
+               1.   Set |extraPoint|'s [=linear easing point/input=] to whichever is greater:
+                    |stop|'s <<linear-stop-length>>'s second <<percentage>> as a number,
+                    or |largestInput|.
+
+               1.   Set |largestInput| to |extraPoint|'s [=linear easing point/input=].
+
+     1.   Otherwise, if |stop| is the first [=list/item=] in |stopList|,
+          then set |point|'s [=linear easing point/input=] to 0.
+
+     1.   Otherwise, if |stop| is the last [=list/item=] in |stopList|,
+          then set |point|'s [=linear easing point/input=] to 1.
+
+1.   For runs of [=list/items=] in |function|'s [=linear easing function/points=] that have a null [=linear easing point/input=],
+     assign a number to the [=linear easing point/input=] by linearly interpolating between the previous and next [=linear easing function/points=] that have a non-null [=linear easing point/input=].
+
+1.   Return |function|.
+
+</section>
+
+<h3 id="the-linear-easing-keyword">The linear easing keyword: ''linear''</h3>
+
+The <dfn dfn-type=value for=easing-function>linear</dfn> keyword is equivalent to ''linear()''.
 
 <h3 id=cubic-bezier-easing-functions oldids=cubic-bezier-timing-functions>Cubic
 B&eacute;zier easing functions: