Concat

1- Install the package and add it to the project dependencies

npm install gulp-concat --save-dev

2- Replace all of the JavaScript files you’re using in your project with one JavaScript file. Call it app.js

3- Add the gulp-concat as a task

var concat = require('gulp-concat');

gulp.task("concat", function() {
  gulp.src([
           'js/jquer.js',
           'js/sticky/jquer.sticky.js',
           'js/main,js'])
  .pipe(concat("app.js"))
  .pip(gulp.dest("js"))
});

4. Run the concat task

gulp concat

• gulp.src([array_of_files])
  Specify source files. This method can take a string or an array as it’s first parameter.
  The order you provide files to gulp.src does not matter.
• pipe(concat("destination_file"))
  Destination file name. The pipe method gets the readable stream of data to our next method.
• pip(gulp.dest("destination_folder"))
  Destination foder. Gulp will overwrite files when the file stream is output using gulp.dest. Therefore, use the Rename package.

Uglify

JavaScript Minification with Uglify

npm install gulp-uglify --save-dev