diff --git a/src/app_helper.h b/src/app_helper.h
index 5d1624b7..aaf1b6fb 100644
--- a/src/app_helper.h
+++ b/src/app_helper.h
@@ -94,7 +94,8 @@ std::chrono::steady_clock::time_point get_time();
 void print_timer();
 
 // Setting true will print characters with ANSI color escape codes
-// when printing SPDY frames. This function changes a static variable.
+// when printing HTTP2 frames. This function changes a static
+// variable.
 void set_color_output(bool f);
 
 } // namespace nghttp2
diff --git a/src/shrpx.cc b/src/shrpx.cc
index 28a22ac4..73369da2 100644
--- a/src/shrpx.cc
+++ b/src/shrpx.cc
@@ -344,15 +344,15 @@ void fill_default_config()
   mod_config()->private_key_passwd = 0;
   mod_config()->cert_file = 0;
 
-  // Read timeout for SPDY upstream connection
+  // Read timeout for HTTP2 upstream connection
   mod_config()->http2_upstream_read_timeout.tv_sec = 180;
   mod_config()->http2_upstream_read_timeout.tv_usec = 0;
 
-  // Read timeout for non-SPDY upstream connection
+  // Read timeout for non-HTTP2 upstream connection
   mod_config()->upstream_read_timeout.tv_sec = 180;
   mod_config()->upstream_read_timeout.tv_usec = 0;
 
-  // Write timeout for SPDY/non-SPDY upstream connection
+  // Write timeout for HTTP2/non-HTTP2 upstream connection
   mod_config()->upstream_write_timeout.tv_sec = 60;
   mod_config()->upstream_write_timeout.tv_usec = 0;
 
diff --git a/src/shrpx_client_handler.h b/src/shrpx_client_handler.h
index 97093c6e..abbc6f99 100644
--- a/src/shrpx_client_handler.h
+++ b/src/shrpx_client_handler.h
@@ -84,7 +84,7 @@ private:
   bool should_close_after_write_;
   std::set<DownstreamConnection*> dconn_pool_;
   // Shared HTTP2 session for each thread. NULL if backend is not
-  // SPDY. Not deleted by this object.
+  // HTTP2. Not deleted by this object.
   Http2Session *http2session_;
   // The number of bytes of HTTP/2.0 client connection header to read
   size_t left_connhd_len_;
diff --git a/src/shrpx_downstream.h b/src/shrpx_downstream.h
index b074dfd8..c78188da 100644
--- a/src/shrpx_downstream.h
+++ b/src/shrpx_downstream.h
@@ -58,7 +58,7 @@ public:
   void pause_read(IOCtrlReason reason);
   int resume_read(IOCtrlReason reason);
   void force_resume_read();
-  // Set stream ID for downstream SPDY connection.
+  // Set stream ID for downstream HTTP2 connection.
   void set_downstream_stream_id(int32_t stream_id);
   int32_t get_downstream_stream_id() const;
 
@@ -213,9 +213,9 @@ private:
   Headers response_headers_;
   bool response_header_key_prev_;
   // This buffer is used to temporarily store downstream response
-  // body. Spdylay reads data from this in the callback.
+  // body. nghttp2 library reads data from this in the callback.
   evbuffer *response_body_buf_;
-  // RST_STREAM error_code from downstream SPDY connection
+  // RST_STREAM error_code from downstream HTTP2 connection
   nghttp2_error_code response_rst_stream_error_code_;
   int32_t recv_window_size_;
 };
diff --git a/src/shrpx_http2_upstream.cc b/src/shrpx_http2_upstream.cc
index a05cbfe1..c009197e 100644
--- a/src/shrpx_http2_upstream.cc
+++ b/src/shrpx_http2_upstream.cc
@@ -45,7 +45,7 @@ using namespace nghttp2;
 namespace shrpx {
 
 namespace {
-const size_t SHRPX_SPDY_UPSTREAM_OUTPUT_UPPER_THRES = 64*1024;
+const size_t SHRPX_HTTP2_UPSTREAM_OUTPUT_UPPER_THRES = 64*1024;
 } // namespace
 
 namespace {
@@ -59,7 +59,7 @@ ssize_t send_callback(nghttp2_session *session,
   auto bev = handler->get_bev();
   auto output = bufferevent_get_output(bev);
   // Check buffer length and return WOULDBLOCK if it is large enough.
-  if(evbuffer_get_length(output) > SHRPX_SPDY_UPSTREAM_OUTPUT_UPPER_THRES) {
+  if(evbuffer_get_length(output) > SHRPX_HTTP2_UPSTREAM_OUTPUT_UPPER_THRES) {
     return NGHTTP2_ERR_WOULDBLOCK;
   }
 
@@ -539,7 +539,7 @@ int Http2Upstream::on_read()
        nghttp2_session_want_write(session_) == 0 &&
        evbuffer_get_length(bufferevent_get_output(handler_->get_bev())) == 0) {
       if(LOG_ENABLED(INFO)) {
-        ULOG(INFO, this) << "No more read/write for this SPDY session";
+        ULOG(INFO, this) << "No more read/write for this HTTP2 session";
       }
       rv = -1;
     }
@@ -565,7 +565,7 @@ int Http2Upstream::send()
        nghttp2_session_want_write(session_) == 0 &&
        evbuffer_get_length(bufferevent_get_output(handler_->get_bev())) == 0) {
       if(LOG_ENABLED(INFO)) {
-        ULOG(INFO, this) << "No more read/write for this SPDY session";
+        ULOG(INFO, this) << "No more read/write for this HTTP2 session";
       }
       rv = -1;
     }
@@ -590,7 +590,7 @@ void downstream_readcb(bufferevent *bev, void *ptr)
   auto downstream = dconn->get_downstream();
   auto upstream = static_cast<Http2Upstream*>(downstream->get_upstream());
   if(downstream->get_request_state() == Downstream::STREAM_CLOSED) {
-    // If upstream SPDY stream was closed, we just close downstream,
+    // If upstream HTTP2 stream was closed, we just close downstream,
     // because there is no consumer now. Downstream connection is also
     // closed in this case.
     upstream->remove_downstream(downstream);
@@ -1005,7 +1005,7 @@ int Http2Upstream::on_downstream_body(Downstream *downstream,
   nghttp2_session_resume_data(session_, downstream->get_stream_id());
 
   size_t bodylen = evbuffer_get_length(body);
-  if(bodylen > SHRPX_SPDY_UPSTREAM_OUTPUT_UPPER_THRES) {
+  if(bodylen > SHRPX_HTTP2_UPSTREAM_OUTPUT_UPPER_THRES) {
     downstream->pause_read(SHRPX_NO_BUFFER);
   }
 
diff --git a/src/shrpx_https_upstream.cc b/src/shrpx_https_upstream.cc
index c65b44e5..1670ffbe 100644
--- a/src/shrpx_https_upstream.cc
+++ b/src/shrpx_https_upstream.cc
@@ -422,8 +422,8 @@ void https_downstream_readcb(bufferevent *bev, void *ptr)
           }
         }
       } else if(downstream->get_upgraded()) {
-        // This path is effectively only taken for SPDY downstream
-        // because only SPDY downstream sets response_state to
+        // This path is effectively only taken for HTTP2 downstream
+        // because only HTTP2 downstream sets response_state to
         // MSG_COMPLETE and this function. For HTTP downstream, EOF
         // from tunnel connection is handled on
         // https_downstream_eventcb.
diff --git a/src/shrpx_log.h b/src/shrpx_log.h
index 0a58c8be..3379d55e 100644
--- a/src/shrpx_log.h
+++ b/src/shrpx_log.h
@@ -64,9 +64,9 @@ namespace shrpx {
 #define DCLOG(SEVERITY, DCONN)                                          \
   (Log(SEVERITY, __FILE__, __LINE__) << "[DCONN:" << DCONN << "] ")
 
-// Downstream SPDY session log
-#define SSLOG(SEVERITY, SPDY)                                           \
-  (Log(SEVERITY, __FILE__, __LINE__) << "[DSPDY:" << SPDY << "] ")
+// Downstream HTTP2 session log
+#define SSLOG(SEVERITY, HTTP2)                                           \
+  (Log(SEVERITY, __FILE__, __LINE__) << "[DHTTP2:" << HTTP2 << "] ")
 
 enum SeverityLevel {
   INFO, WARNING, ERROR, FATAL
diff --git a/src/shrpx_spdy_upstream.cc b/src/shrpx_spdy_upstream.cc
index 4cb9b91a..ae0691d5 100644
--- a/src/shrpx_spdy_upstream.cc
+++ b/src/shrpx_spdy_upstream.cc
@@ -1,5 +1,5 @@
 /*
- * Spdylay - SPDY Library
+ * nghttp2 - HTTP/2.0 C Library
  *
  * Copyright (c) 2012 Tatsuhiro Tsujikawa
  *
diff --git a/src/shrpx_spdy_upstream.h b/src/shrpx_spdy_upstream.h
index e650a8f7..a499d82a 100644
--- a/src/shrpx_spdy_upstream.h
+++ b/src/shrpx_spdy_upstream.h
@@ -1,5 +1,5 @@
 /*
- * Spdylay - SPDY Library
+ * nghttp2 - HTTP/2.0 C Library
  *
  * Copyright (c) 2012 Tatsuhiro Tsujikawa
  *