diff --git a/modules/androidcamera/src/camera_activity.cpp b/modules/androidcamera/src/camera_activity.cpp
index 5445c4e37..c65fd7d3b 100644
--- a/modules/androidcamera/src/camera_activity.cpp
+++ b/modules/androidcamera/src/camera_activity.cpp
@@ -4,7 +4,6 @@
 #include <dirent.h>
 #include <android/log.h>
 #include <cctype>
-#include <string>
 #include <vector>
 #include <algorithm>
 #include <opencv2/core/version.hpp>
diff --git a/modules/core/doc/basic_structures.rst b/modules/core/doc/basic_structures.rst
index d9cc30331..715fafb9a 100644
--- a/modules/core/doc/basic_structures.rst
+++ b/modules/core/doc/basic_structures.rst
@@ -2457,13 +2457,13 @@ Algorithm::name
 ---------------
 Returns the algorithm name
 
-.. ocv:function:: string Algorithm::name() const
+.. ocv:function:: String Algorithm::name() const
 
 Algorithm::get
 --------------
 Returns the algorithm parameter
 
-.. ocv:function:: template<typename _Tp> typename ParamType<_Tp>::member_type Algorithm::get(const string& name) const
+.. ocv:function:: template<typename _Tp> typename ParamType<_Tp>::member_type Algorithm::get(const String& name) const
 
     :param name: The parameter name.
 
@@ -2472,7 +2472,7 @@ The method returns value of the particular parameter. Since the compiler can not
     * myalgo.get<int>("param_name")
     * myalgo.get<double>("param_name")
     * myalgo.get<bool>("param_name")
-    * myalgo.get<string>("param_name")
+    * myalgo.get<String>("param_name")
     * myalgo.get<Mat>("param_name")
     * myalgo.get<vector<Mat> >("param_name")
     * myalgo.get<Algorithm>("param_name") (it returns Ptr<Algorithm>).
@@ -2529,13 +2529,13 @@ Algorithm::getList
 ------------------
 Returns the list of registered algorithms
 
-.. ocv:function:: void Algorithm::getList(vector<string>& algorithms)
+.. ocv:function:: void Algorithm::getList(vector<String>& algorithms)
 
     :param algorithms: The output vector of algorithm names.
 
 This static method returns the list of registered algorithms in alphabetical order. Here is how to use it ::
 
-    vector<string> algorithms;
+    vector<String> algorithms;
     Algorithm::getList(algorithms);
     cout << "Algorithms: " << algorithms.size() << endl;
     for (size_t i=0; i < algorithms.size(); i++)
diff --git a/modules/core/doc/command_line_parser.rst b/modules/core/doc/command_line_parser.rst
index ed77e8c47..09cbd207d 100644
--- a/modules/core/doc/command_line_parser.rst
+++ b/modules/core/doc/command_line_parser.rst
@@ -63,8 +63,8 @@ The sample below demonstrates how to use CommandLineParser:
 
     use_time_stamp = parser.has("timestamp");
 
-    cv::String img1 = parser.get<string>(0);
-    cv::String img2 = parser.get<string>(1);
+    cv::String img1 = parser.get<cv::String>(0);
+    cv::String img2 = parser.get<cv::String>(1);
 
     int repeat = parser.get<int>(2);
 
diff --git a/modules/core/include/opencv2/core.hpp b/modules/core/include/opencv2/core.hpp
index 86447bf8c..08479152b 100644
--- a/modules/core/include/opencv2/core.hpp
+++ b/modules/core/include/opencv2/core.hpp
@@ -62,7 +62,6 @@
 #include <complex>
 #include <map>
 #include <new>
-#include <string>
 #include <vector>
 #include <sstream>
 #endif // SKIP_INCLUDES
diff --git a/modules/core/src/gl_core_3_1.cpp b/modules/core/src/gl_core_3_1.cpp
index e8f371892..1b46205f0 100644
--- a/modules/core/src/gl_core_3_1.cpp
+++ b/modules/core/src/gl_core_3_1.cpp
@@ -1,4 +1,3 @@
-#include <string>
 #include <sstream>
 #include "cvconfig.h"
 #include "opencv2/core.hpp"
diff --git a/modules/flann/include/opencv2/flann/flann_base.hpp b/modules/flann/include/opencv2/flann/flann_base.hpp
index ce5664518..98c33cf6c 100644
--- a/modules/flann/include/opencv2/flann/flann_base.hpp
+++ b/modules/flann/include/opencv2/flann/flann_base.hpp
@@ -32,7 +32,6 @@
 #define OPENCV_FLANN_BASE_HPP_
 
 #include <vector>
-#include <string>
 #include <cassert>
 #include <cstdio>
 
diff --git a/modules/flann/include/opencv2/flann/hierarchical_clustering_index.h b/modules/flann/include/opencv2/flann/hierarchical_clustering_index.h
index ce2d62245..b8b16941f 100644
--- a/modules/flann/include/opencv2/flann/hierarchical_clustering_index.h
+++ b/modules/flann/include/opencv2/flann/hierarchical_clustering_index.h
@@ -32,7 +32,6 @@
 #define OPENCV_FLANN_HIERARCHICAL_CLUSTERING_INDEX_H_
 
 #include <algorithm>
-#include <string>
 #include <map>
 #include <cassert>
 #include <limits>
diff --git a/modules/flann/include/opencv2/flann/kmeans_index.h b/modules/flann/include/opencv2/flann/kmeans_index.h
index 3fea956a7..c3b1fd5b8 100644
--- a/modules/flann/include/opencv2/flann/kmeans_index.h
+++ b/modules/flann/include/opencv2/flann/kmeans_index.h
@@ -32,7 +32,6 @@
 #define OPENCV_FLANN_KMEANS_INDEX_H_
 
 #include <algorithm>
-#include <string>
 #include <map>
 #include <cassert>
 #include <limits>
diff --git a/modules/flann/include/opencv2/flann/nn_index.h b/modules/flann/include/opencv2/flann/nn_index.h
index d14e83a92..381d4bc3c 100644
--- a/modules/flann/include/opencv2/flann/nn_index.h
+++ b/modules/flann/include/opencv2/flann/nn_index.h
@@ -31,8 +31,6 @@
 #ifndef OPENCV_FLANN_NNINDEX_H
 #define OPENCV_FLANN_NNINDEX_H
 
-#include <string>
-
 #include "general.h"
 #include "matrix.h"
 #include "result_set.h"
diff --git a/modules/gpu/src/nvidia/NCVHaarObjectDetection.hpp b/modules/gpu/src/nvidia/NCVHaarObjectDetection.hpp
index b11256641..8c7675fb6 100644
--- a/modules/gpu/src/nvidia/NCVHaarObjectDetection.hpp
+++ b/modules/gpu/src/nvidia/NCVHaarObjectDetection.hpp
@@ -58,7 +58,6 @@
 #ifndef _ncvhaarobjectdetection_hpp_
 #define _ncvhaarobjectdetection_hpp_
 
-#include <string>
 #include "NCV.hpp"
 
 
diff --git a/modules/gpu/src/nvidia/core/NCV.cu b/modules/gpu/src/nvidia/core/NCV.cu
index f1b2194f8..b8fda83e0 100644
--- a/modules/gpu/src/nvidia/core/NCV.cu
+++ b/modules/gpu/src/nvidia/core/NCV.cu
@@ -41,7 +41,6 @@
 
 
 #include <iostream>
-#include <string>
 #include <vector>
 #include "NCV.hpp"
 
diff --git a/modules/gpu/src/precomp.hpp b/modules/gpu/src/precomp.hpp
index caa46cfc8..41f5af5c5 100644
--- a/modules/gpu/src/precomp.hpp
+++ b/modules/gpu/src/precomp.hpp
@@ -64,7 +64,6 @@
 #include <deque>
 #include <stdexcept>
 #include <memory>
-#include <string>
 
 #include "opencv2/gpu.hpp"
 #include "opencv2/imgproc.hpp"
diff --git a/modules/highgui/src/cap_pvapi.cpp b/modules/highgui/src/cap_pvapi.cpp
index 9e46dabf6..6ed3aea84 100644
--- a/modules/highgui/src/cap_pvapi.cpp
+++ b/modules/highgui/src/cap_pvapi.cpp
@@ -63,7 +63,6 @@
 #  include <unistd.h>
 #endif
 
-#include <string>
 //#include <arpa/inet.h>
 
 #define MAX_CAMERAS 10
diff --git a/modules/ml/include/opencv2/ml.hpp b/modules/ml/include/opencv2/ml.hpp
index d3a690c96..5c1591a7e 100644
--- a/modules/ml/include/opencv2/ml.hpp
+++ b/modules/ml/include/opencv2/ml.hpp
@@ -47,7 +47,6 @@
 #ifdef __cplusplus
 
 #include <map>
-#include <string>
 #include <iostream>
 
 // Apple defines a check() macro somewhere in the debug headers
diff --git a/modules/objdetect/doc/latent_svm.rst b/modules/objdetect/doc/latent_svm.rst
index 86fb0edc1..8362dfb11 100644
--- a/modules/objdetect/doc/latent_svm.rst
+++ b/modules/objdetect/doc/latent_svm.rst
@@ -204,7 +204,7 @@ Two types of constructors.
 
 .. ocv:function:: LatentSvmDetector::LatentSvmDetector()
 
-.. ocv:function:: LatentSvmDetector::LatentSvmDetector(const vector<string>& filenames, const vector<string>& classNames=vector<string>())
+.. ocv:function:: LatentSvmDetector::LatentSvmDetector(const vector<String>& filenames, const vector<String>& classNames=vector<String>())
 
 
 
@@ -228,7 +228,7 @@ LatentSvmDetector::load
 -----------------------
 Load the trained models from given ``.xml`` files and return ``true`` if at least one model was loaded.
 
-.. ocv:function:: bool LatentSvmDetector::load( const vector<string>& filenames, const vector<string>& classNames=vector<string>() )
+.. ocv:function:: bool LatentSvmDetector::load( const vector<String>& filenames, const vector<String>& classNames=vector<String>() )
 
     :param filenames: A set of filenames storing the trained detectors (models). Each file contains one model. See examples of such files here /opencv_extra/testdata/cv/latentsvmdetector/models_VOC2007/.
 
@@ -250,7 +250,7 @@ LatentSvmDetector::getClassNames
 --------------------------------
 Return the class (model) names that were passed in constructor or method ``load`` or extracted from models filenames in those methods.
 
-.. ocv:function:: const vector<string>& LatentSvmDetector::getClassNames() const
+.. ocv:function:: const vector<String>& LatentSvmDetector::getClassNames() const
 
 LatentSvmDetector::getClassCount
 --------------------------------
diff --git a/modules/objdetect/src/cascadedetect.cpp b/modules/objdetect/src/cascadedetect.cpp
index 20b6a81f9..035944e19 100644
--- a/modules/objdetect/src/cascadedetect.cpp
+++ b/modules/objdetect/src/cascadedetect.cpp
@@ -44,8 +44,6 @@
 
 #include "cascadedetect.hpp"
 
-#include <string>
-
 #if defined (LOG_CASCADE_STATISTIC)
 struct Logger
 {
diff --git a/modules/ocl/src/haar.cpp b/modules/ocl/src/haar.cpp
index 83cfb5a6f..6b8016a76 100644
--- a/modules/ocl/src/haar.cpp
+++ b/modules/ocl/src/haar.cpp
@@ -49,7 +49,6 @@
 
 #include "precomp.hpp"
 #include <stdio.h>
-#include <string>
 
 using namespace cv;
 using namespace cv::ocl;
diff --git a/modules/softcascade/src/octave.cpp b/modules/softcascade/src/octave.cpp
index d14e015e9..e1e46c5b1 100644
--- a/modules/softcascade/src/octave.cpp
+++ b/modules/softcascade/src/octave.cpp
@@ -42,7 +42,6 @@
 
 #include "precomp.hpp"
 #include <queue>
-#include <string>
 
 using cv::InputArray;
 using cv::OutputArray;
diff --git a/modules/superres/src/frame_source.cpp b/modules/superres/src/frame_source.cpp
index 61f2ebde3..e15cc114c 100644
--- a/modules/superres/src/frame_source.cpp
+++ b/modules/superres/src/frame_source.cpp
@@ -83,7 +83,7 @@ Ptr<FrameSource> cv::superres::createFrameSource_Empty()
 
 #ifndef HAVE_OPENCV_HIGHGUI
 
-Ptr<FrameSource> cv::superres::createFrameSource_Video(const string& fileName)
+Ptr<FrameSource> cv::superres::createFrameSource_Video(const String& fileName)
 {
     (void) fileName;
     CV_Error(CV_StsNotImplemented, "The called functionality is disabled for current build or platform");
@@ -190,7 +190,7 @@ Ptr<FrameSource> cv::superres::createFrameSource_Camera(int deviceId)
 
 #ifndef HAVE_OPENCV_GPU
 
-Ptr<FrameSource> cv::superres::createFrameSource_Video_GPU(const string& fileName)
+Ptr<FrameSource> cv::superres::createFrameSource_Video_GPU(const String& fileName)
 {
     (void) fileName;
     CV_Error(CV_StsNotImplemented, "The called functionality is disabled for current build or platform");
diff --git a/modules/videostab/include/opencv2/videostab/frame_source.hpp b/modules/videostab/include/opencv2/videostab/frame_source.hpp
index dc8d164b2..204323fa7 100644
--- a/modules/videostab/include/opencv2/videostab/frame_source.hpp
+++ b/modules/videostab/include/opencv2/videostab/frame_source.hpp
@@ -44,7 +44,6 @@
 #define __OPENCV_VIDEOSTAB_FRAME_SOURCE_HPP__
 
 #include <vector>
-#include <string>
 #include "opencv2/core.hpp"
 
 namespace cv
diff --git a/modules/videostab/include/opencv2/videostab/global_motion.hpp b/modules/videostab/include/opencv2/videostab/global_motion.hpp
index d4a83a76b..4b902ae1c 100644
--- a/modules/videostab/include/opencv2/videostab/global_motion.hpp
+++ b/modules/videostab/include/opencv2/videostab/global_motion.hpp
@@ -44,7 +44,6 @@
 #define __OPENCV_VIDEOSTAB_GLOBAL_MOTION_HPP__
 
 #include <vector>
-#include <string>
 #include <fstream>
 #include "opencv2/core.hpp"
 #include "opencv2/features2d.hpp"