diff --git a/HISTORY.txt b/HISTORY.txt
index 74c251e6..04717e2a 100644
--- a/HISTORY.txt
+++ b/HISTORY.txt
@@ -737,7 +737,7 @@
 6.0.0:
  - New locking functionality — support for multiple hashes per release!
  - Hashes are now default, everywhere, once again! We figured it out :)
- - Pipenv talks to the PyPi (Warehouse) API now for grabbing hashes.
+ - Pipenv talks to the PyPI (Warehouse) API now for grabbing hashes.
  - --hashes flag removed.
  - Upgraded to Pipfile spec 2.
  - New --legacy mode for lock.
diff --git a/README.md b/README.md
index 9e23f148..f6af5917 100644
--- a/README.md
+++ b/README.md
@@ -181,8 +181,8 @@ Fish is the best shell. You should use it.
                  provided in Pipfile.
       clean      Uninstalls all packages not specified in Pipfile.lock.
       graph      Displays currently–installed dependency graph information.
-      install    Installs provided packages and adds them to Pipfile, or (if none
-                 is given), installs all packages.
+      install    Installs provided packages and adds them to Pipfile, or (if no
+                 packages are given), installs all packages from Pipfile.
       lock       Generates Pipfile.lock.
       open       View a given module in your editor.
       run        Spawns a command installed into the virtualenv.
diff --git a/docs/basics.rst b/docs/basics.rst
index 559f7570..5d41249f 100644
--- a/docs/basics.rst
+++ b/docs/basics.rst
@@ -287,7 +287,7 @@ The user can provide these additional parameters:
               folder is encoded into a "slug value" and appended to ensure the virtualenv name
               is unique.
 
-    - ``--dev`` — Install both ``develop`` and ``default`` packages from ``Pipfile.lock``.
+    - ``--dev`` — Install both ``develop`` and ``default`` packages from ``Pipfile``.
     - ``--system`` — Use the system ``pip`` command rather than the one from your virtualenv.
     - ``--ignore-pipfile`` — Ignore the ``Pipfile`` and install from the ``Pipfile.lock``.
     - ``--skip-lock`` — Ignore the ``Pipfile.lock`` and install from the ``Pipfile``. In addition, do not write out a ``Pipfile.lock`` reflecting changes to the ``Pipfile``.
diff --git a/news/2844.doc b/news/2844.doc
new file mode 100644
index 00000000..28f26514
--- /dev/null
+++ b/news/2844.doc
@@ -0,0 +1 @@
+Clarify `pipenv install` documentation
diff --git a/pipenv/cli/command.py b/pipenv/cli/command.py
index f6c0d133..b552778f 100644
--- a/pipenv/cli/command.py
+++ b/pipenv/cli/command.py
@@ -209,7 +209,7 @@ def cli(
 
 
 @cli.command(
-    short_help="Installs provided packages and adds them to Pipfile, or (if none is given), installs all packages.",
+    short_help="Installs provided packages and adds them to Pipfile, or (if no packages are given), installs all packages from Pipfile.",
     context_settings=dict(ignore_unknown_options=True, allow_extra_args=True),
 )
 @system_option
@@ -224,7 +224,7 @@ def install(
     state,
     **kwargs
 ):
-    """Installs provided packages and adds them to Pipfile, or (if none is given), installs all packages."""
+    """Installs provided packages and adds them to Pipfile, or (if no packages are given), installs all packages from Pipfile."""
     from ..core import do_install
 
     retcode = do_install(
diff --git a/pipenv/cli/options.py b/pipenv/cli/options.py
index cf9daa19..99fc5344 100644
--- a/pipenv/cli/options.py
+++ b/pipenv/cli/options.py
@@ -166,7 +166,7 @@ def dev_option(f):
         state.installstate.dev = value
         return value
     return option("--dev", "-d", is_flag=True, default=False, type=click_booltype,
-                    help="Install package(s) in [dev-packages].", callback=callback,
+                    help="Install both develop and default packages.", callback=callback,
                     expose_value=False)(f)
 
 
diff --git a/setup.py b/setup.py
index ea5af031..4a6b9389 100644
--- a/setup.py
+++ b/setup.py
@@ -92,7 +92,7 @@ class UploadCommand(Command):
             pass
         self.status("Building Source distribution…")
         os.system("{0} setup.py sdist bdist_wheel".format(sys.executable))
-        self.status("Uploading the package to PyPi via Twine…")
+        self.status("Uploading the package to PyPI via Twine…")
         os.system("twine upload dist/*")
         self.status("Pushing git tags…")
         os.system("git tag v{0}".format(about["__version__"]))
diff --git a/tests/pytest-pypi/setup.py b/tests/pytest-pypi/setup.py
index 3341b098..87f6b752 100644
--- a/tests/pytest-pypi/setup.py
+++ b/tests/pytest-pypi/setup.py
@@ -42,7 +42,7 @@ class UploadCommand(Command):
         self.status('Building Source and Wheel (universal) distribution…')
         os.system('{0} setup.py sdist bdist_wheel --universal'.format(sys.executable))
 
-        self.status('Uploading the package to PyPi via Twine…')
+        self.status('Uploading the package to PyPI via Twine…')
         os.system('twine upload dist/*')
 
         self.status('Pushing git tags…')