1. Checkbox

                         <input type="checkbox" name="chk" value="">
                 

a checkbox should have name and value

2. with label

                 <div class="form-group">
                        <div class="checkbox">
                                <label> <input type="checkbox" name="chk[]" value=""> Option 1</label>
                        </div>
                        <div class="checkbox">
                              <label> <input type="checkbox" name="chk[]" value=""> Option 2</label>
                        </div>
                  </div>

                

3. Inline Checkbox

                <label class="checkbox-inline"><input type="checkbox" value="">Option 1</label>
                      <label class="checkbox-inline"><input type="checkbox" value="">Option 2</label>
                      <label class="checkbox-inline"><input type="checkbox" value="">Option 3</label>