diff --git a/lib/phoenix/pubsub/pg2.ex b/lib/phoenix/pubsub/pg2.ex
index 83907490..330e79d6 100644
--- a/lib/phoenix/pubsub/pg2.ex
+++ b/lib/phoenix/pubsub/pg2.ex
@@ -72,7 +72,7 @@ defmodule Phoenix.PubSub.PG2 do
         :"#{adapter_name}_#{number}"
       end
 
-    # Use `adapter_name` for the first in the pool for backwards compatability
+    # Use `adapter_name` for the first in the pool for backwards compatibility
     # with v2.0 when the pool_size is 1.
     groups = [adapter_name | groups]
 
diff --git a/lib/phoenix/tracker.ex b/lib/phoenix/tracker.ex
index 8fd9ab6b..676b5e6d 100644
--- a/lib/phoenix/tracker.ex
+++ b/lib/phoenix/tracker.ex
@@ -196,7 +196,7 @@ defmodule Phoenix.Tracker do
     * `server_name` - The registered name of the tracker server
     * `topic` - The `Phoenix.PubSub` topic
 
-  Returns a lists of presences in key/metadata tuple pairs.
+  Returns a list of presences in key/metadata tuple pairs.
 
   ## Examples
 
@@ -217,12 +217,12 @@ defmodule Phoenix.Tracker do
     * `topic` - The `Phoenix.PubSub` topic
     * `key` - The key of the presence
 
-  Returns a lists of presence metadata.
+  Returns a list of presence metadata.
 
   ## Examples
 
       iex> Phoenix.Tracker.get_by_key(MyTracker, "lobby", "user1")
-      [{#PID<0.88.0>, %{name: "User 1"}, {#PID<0.89.0>, %{name: "User 1"}]
+      [{#PID<0.88.0>, %{name: "User 1"}}, {#PID<0.89.0>, %{name: "User 1"}}]
   """
   @spec get_by_key(atom, topic, term) :: [{pid, map}]
   def get_by_key(tracker_name, topic, key) do
diff --git a/lib/phoenix/tracker/delta_generation.ex b/lib/phoenix/tracker/delta_generation.ex
index afa90d7a..d1161f0e 100644
--- a/lib/phoenix/tracker/delta_generation.ex
+++ b/lib/phoenix/tracker/delta_generation.ex
@@ -10,7 +10,7 @@ defmodule Phoenix.Tracker.DeltaGeneration do
   """
   @spec extract(State.t, [State.delta], State.name, State.context) :: State.delta | State.t
   def extract(%State{mode: :normal} = state, generations, remote_ref, remote_context) do
-    case delta_fullfilling_clock(generations, remote_context) do
+    case delta_fulfilling_clock(generations, remote_context) do
       {delta, index} ->
         if index, do: Logger.debug "#{inspect state.replica}: sending delta generation #{index + 1}"
         State.extract(delta, remote_ref, remote_context)
@@ -54,7 +54,7 @@ defmodule Phoenix.Tracker.DeltaGeneration do
     end)
   end
 
-  defp delta_fullfilling_clock(generations, remote_context) do
+  defp delta_fulfilling_clock(generations, remote_context) do
     generations
     |> Enum.with_index()
     |> Enum.find(fn {%State{range: {local_start, local_end}}, _} ->
diff --git a/test/phoenix/tracker/shard_replication_test.exs b/test/phoenix/tracker/shard_replication_test.exs
index 0a6fed5e..c0ec0780 100644
--- a/test/phoenix/tracker/shard_replication_test.exs
+++ b/test/phoenix/tracker/shard_replication_test.exs
@@ -127,7 +127,7 @@ defmodule Phoenix.Tracker.ShardReplicationTest do
     refute {@node1, node1_node} in get_values(@node2, node2_shard)
   end
 
-  # TODO split into multiple testscases
+  # TODO split into multiple test cases
   test "tempdowns with nodeups of new vsn, and permdowns",
     %{shard: shard, topic: topic, tracker: tracker} do