diff --git a/app/helpers/admin/configs_helper.rb b/app/helpers/admin/configs_helper.rb
index 68f53fc2..4e100751 100644
--- a/app/helpers/admin/configs_helper.rb
+++ b/app/helpers/admin/configs_helper.rb
@@ -17,10 +17,10 @@ module Admin::ConfigsHelper
     config_input_field_options form, key, options[:input_html]
     config_input_tooltip_options form, key, options[:input_html]
     if options[:as] == :boolean
-      options[:input_html][:checked] = 'checked' if v=options[:input_html].delete(:value) and v!='false'
+      options[:input_html][:checked] = 'checked' if v=options[:input_html].delete(:value) && v!='false'
       options[:checked_value] = 'true' if options[:checked_value].nil?
       options[:unchecked_value] = 'false' if options[:unchecked_value].nil?
-    elsif options[:collection] or options[:as] == :select
+    elsif options[:collection] || options[:as] == :select
       options[:selected] = options[:input_html].delete(:value)
       return form.input key, options, &block
     elsif options[:as] == :time_zone
@@ -53,7 +53,7 @@ module Admin::ConfigsHelper
     if options[:as] == :boolean
       checked_value = options.delete(:checked_value) || 'true'
       unchecked_value = options.delete(:unchecked_value) || 'false'
-      options[:checked] = 'checked' if v=options.delete(:value) and v!='false'
+      options[:checked] = 'checked' if v=options.delete(:value) && v!='false'
       form.hidden_field(key, value: unchecked_value, as: :hidden) + form.check_box(key, options, checked_value, false)
     elsif options[:as] == :select_recurring
       options[:value] = FoodsoftDateUtil.rule_from(options[:value])
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index f960a07e..cbcdf9f2 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -16,7 +16,7 @@ module ApplicationHelper
   end
 
   def format_datetime_timespec(time, format)
-    I18n.l(time, :format => format) unless (time.nil? or format.nil?)
+    I18n.l(time, :format => format) unless (time.nil? || format.nil?)
   end
   
   # Creates ajax-controlled-links for pagination
@@ -92,7 +92,7 @@ module ApplicationHelper
     if options[:short]
       desc = options[:desc]
       desc ||= model.human_attribute_name("#{attribute}_desc".to_sym, options.merge({fallback: true, default: '', count: 2}))
-      desc.blank? and desc = s
+      desc.blank? && desc = s
       sshort = model.human_attribute_name("#{attribute}_short".to_sym, options.merge({fallback: true, default: '', count: 2}))
       s = raw "<abbr title='#{desc}'>#{sshort}</abbr>" unless sshort.blank?
     end
@@ -187,7 +187,7 @@ module ApplicationHelper
   # render base errors in a form after failed validation
   # http://railsapps.github.io/twitter-bootstrap-rails.html
   def base_errors resource
-    return '' if (resource.errors.empty?) or (resource.errors[:base].empty?)
+    return '' if resource.errors.empty? || resource.errors[:base].empty?
     messages = resource.errors[:base].map { |msg| content_tag(:li, msg) }.join
     render :partial => 'shared/base_errors', :locals => {:error_messages => messages}
   end
@@ -197,7 +197,7 @@ module ApplicationHelper
     if user.nil?
       "?"
     elsif FoodsoftConfig[:use_nick]
-      if options[:full] and options[:markup]
+      if options[:full] && options[:markup]
         raw "<b>#{h user.nick}</b> (#{h user.first_name} #{h user.last_name})"
       elsif options[:full]
         "#{user.nick} (#{user.first_name} #{user.last_name})"
@@ -217,7 +217,7 @@ module ApplicationHelper
 
   # allow truncate to add title when tooltip option is given
   def truncate(text, options={}, &block)
-    return text if not text or text.length <= (options[:length] or 30)
+    return text if !text || text.length <= (options[:length] || 30)
     text_truncated = super(text, options, &block)
     if options[:tooltip]
       content_tag :span, text_truncated, title: text
diff --git a/app/helpers/group_order_articles_helper.rb b/app/helpers/group_order_articles_helper.rb
index 46f2a8cb..c1c8fddb 100644
--- a/app/helpers/group_order_articles_helper.rb
+++ b/app/helpers/group_order_articles_helper.rb
@@ -2,7 +2,7 @@ module GroupOrderArticlesHelper
 
   # return an edit field for a GroupOrderArticle result
   def group_order_article_edit_result(goa)
-    unless goa.group_order.order.finished? and current_user.role_finance?
+    unless goa.group_order.order.finished? && current_user.role_finance?
       goa.result
     else
       simple_form_for goa, remote: true, html: {'data-submit-onchange' => 'changed', class: 'delta-input'} do |f|
diff --git a/app/helpers/group_orders_helper.rb b/app/helpers/group_orders_helper.rb
index bf490903..90282c53 100644
--- a/app/helpers/group_orders_helper.rb
+++ b/app/helpers/group_orders_helper.rb
@@ -11,7 +11,7 @@ module GroupOrdersHelper
   # If the option :show is true, the link is for showing the group_order.
   def link_to_ordering(order, options = {}, &block)
     group_order = order.group_order(current_user.ordergroup)
-    path = if options[:show] and group_order
+    path = if options[:show] && group_order
             group_order_path(group_order)
           elsif group_order
             edit_group_order_path(group_order, :order_id => order.id)
diff --git a/app/helpers/orders_helper.rb b/app/helpers/orders_helper.rb
index d9fb1eb2..30081a1e 100644
--- a/app/helpers/orders_helper.rb
+++ b/app/helpers/orders_helper.rb
@@ -48,12 +48,12 @@ module OrdersHelper
   #   Sensible in tables with multiple columns.
   # @return [String] Text showing unit and unit quantity when applicable.
   def pkg_helper(article, options={})
-    return '' if not article or article.unit_quantity == 1
+    return '' if !article || article.unit_quantity == 1
     uq_text = "× #{article.unit_quantity}"
     uq_text = content_tag(:span, uq_text, class: 'hidden-phone') if options[:soft_uq]
     if options[:plain]
       uq_text
-    elsif options[:icon].nil? or options[:icon]
+    elsif options[:icon].nil? || options[:icon]
       pkg_helper_icon(uq_text)
     else
       pkg_helper_icon(uq_text, tag: :span)
@@ -80,7 +80,7 @@ module OrdersHelper
   
   def receive_input_field(form)
     order_article = form.object
-    units_expected = (order_article.units_billed or order_article.units_to_order) *
+    units_expected = (order_article.units_billed || order_article.units_to_order) *
       1.0 * order_article.article.unit_quantity / order_article.article_price.unit_quantity
     
     input_classes = 'input input-nano units_received'
@@ -117,7 +117,7 @@ module OrdersHelper
   # @param order_or_supplier [Order, Supplier] Order or supplier to link to
   # @return [String] Link to order or supplier, showing its name.
   def supplier_link(order_or_supplier)
-    if order_or_supplier.kind_of?(Order) and order_or_supplier.stockit?
+    if order_or_supplier.kind_of?(Order) && order_or_supplier.stockit?
       link_to(order_or_supplier.name, stock_articles_path).html_safe
     else
       link_to(@order.supplier.name, supplier_path(@order.supplier)).html_safe
diff --git a/app/models/article.rb b/app/models/article.rb
index c3ca0465..e1011b1f 100644
--- a/app/models/article.rb
+++ b/app/models/article.rb
@@ -103,13 +103,13 @@ class Article < ActiveRecord::Base
   def shared_article_changed?(supplier = self.supplier)
     # skip early if the timestamp hasn't changed
     shared_article = self.shared_article(supplier)
-    unless shared_article.nil? or self.shared_updated_on == shared_article.updated_on
+    unless shared_article.nil? || self.shared_updated_on == shared_article.updated_on
       
       # try to convert units
       # convert supplier's price and unit_quantity into fc-size
       new_price, new_unit_quantity = self.convert_units
       new_unit = self.unit
-      unless new_price and new_unit_quantity
+      unless new_price && new_unit_quantity
         # if convertion isn't possible, take shared_article-price/unit_quantity
         new_price, new_unit_quantity, new_unit = shared_article.price, shared_article.unit_quantity, shared_article.unit
       end
@@ -142,7 +142,7 @@ class Article < ActiveRecord::Base
   # compare attributes from different articles. used for auto-synchronization
   # returns array of symbolized unequal attributes
   def self.compare_attributes(attributes)
-    unequal_attributes = attributes.select { |name, values| values[0] != values[1] and not (values[0].blank? and values[1].blank?) }
+    unequal_attributes = attributes.select { |name, values| values[0] != values[1] && !(values[0].blank? && values[1].blank?) }
     unequal_attributes.collect { |pair| pair[0] }
   end
   
@@ -160,10 +160,10 @@ class Article < ActiveRecord::Base
   def convert_units
     if unit != shared_article.unit
       # legacy, used by foodcoops in Germany
-      if shared_article.unit == "KI" and unit == "ST" # 'KI' means a box, with a different amount of items in it
+      if shared_article.unit == "KI" && unit == "ST" # 'KI' means a box, with a different amount of items in it
         # try to match the size out of its name, e.g. "banana 10-12 St" => 10
         new_unit_quantity = /[0-9\-\s]+(St)/.match(shared_article.name).to_s.to_i
-        if new_unit_quantity and new_unit_quantity > 0
+        if new_unit_quantity && new_unit_quantity > 0
           new_price = (shared_article.price/new_unit_quantity.to_f).round(2)
           [new_price, new_unit_quantity]
         else
@@ -172,7 +172,7 @@ class Article < ActiveRecord::Base
       else # use ruby-units to convert
         fc_unit = (::Unit.new(unit) rescue nil)
         supplier_unit = (::Unit.new(shared_article.unit) rescue nil)
-        if fc_unit and supplier_unit and fc_unit =~ supplier_unit
+        if fc_unit && supplier_unit && fc_unit =~ supplier_unit
           conversion_factor = (supplier_unit / fc_unit).to_base.to_r
           new_price = shared_article.price / conversion_factor
           new_unit_quantity = shared_article.unit_quantity * conversion_factor
@@ -225,7 +225,7 @@ class Article < ActiveRecord::Base
     matches = Article.where(name: name, supplier_id: supplier_id, deleted_at: deleted_at, type: type)
     matches = matches.where.not(id: id) unless new_record?
     # supplier should always be there - except, perhaps, on initialization (on seeding)
-    if supplier and (supplier.shared_sync_method.blank? or supplier.shared_sync_method == 'import')
+    if supplier && (supplier.shared_sync_method.blank? || supplier.shared_sync_method == 'import')
       errors.add :name, :taken if matches.any?
     else
       errors.add :name, :taken_with_unit if matches.where(unit: unit, unit_quantity: unit_quantity).any?
diff --git a/app/models/article_category.rb b/app/models/article_category.rb
index 9a2004ae..b28d213b 100644
--- a/app/models/article_category.rb
+++ b/app/models/article_category.rb
@@ -19,14 +19,14 @@ class ArticleCategory < ActiveRecord::Base
   # Find a category that matches a category name; may return nil.
   # TODO more intelligence like remembering earlier associations (global and/or per-supplier)
   def self.find_match(category)
-    return if category.blank? or category.length < 3
+    return if category.blank? || category.length < 3
     c = nil
     ## exact match - not needed, will be returned by next query as well
     #c ||= ArticleCategory.where(name: category).first
     # case-insensitive substring match (take the closest match = shortest)
-    c = ArticleCategory.where('name LIKE ?', "%#{category}%") unless c and c.any?
+    c = ArticleCategory.where('name LIKE ?', "%#{category}%") unless c && c.any?
     # case-insensitive phrase present in category description
-    c = ArticleCategory.where('description LIKE ?', "%#{category}%").select {|s| s.description.match /(^|,)\s*#{category}\s*(,|$)/i} unless c and c.any?
+    c = ArticleCategory.where('description LIKE ?', "%#{category}%").select {|s| s.description.match /(^|,)\s*#{category}\s*(,|$)/i} unless c && c.any?
     # return closest match if there are multiple
     c = c.sort_by {|s| s.name.length}.first if c.respond_to? :sort_by
     c
diff --git a/app/models/group_order_article.rb b/app/models/group_order_article.rb
index 0b37bf8e..6dd55445 100644
--- a/app/models/group_order_article.rb
+++ b/app/models/group_order_article.rb
@@ -36,7 +36,7 @@ class GroupOrderArticle < ActiveRecord::Base
     logger.debug("Current quantity = #{self.quantity}, tolerance = #{self.tolerance}")
 
     # When quantity and tolerance are zero, we don't serve any purpose
-    if quantity == 0 and tolerance == 0
+    if quantity == 0 && tolerance == 0
       logger.debug("Self-destructing since requested quantity and tolerance are zero")
       destroy!
       return
@@ -108,7 +108,7 @@ class GroupOrderArticle < ActiveRecord::Base
   # See description of the ordering algorithm in the general application documentation for details.
   def calculate_result(total = nil)
     # return memoized result unless a total is given
-    return @calculate_result if total.nil? and not @calculate_result.nil?
+    return @calculate_result if total.nil? && !@calculate_result.nil?
 
     quantity = tolerance = total_quantity = 0
 
diff --git a/app/models/order.rb b/app/models/order.rb
index 362d7840..fcca6ef4 100644
--- a/app/models/order.rb
+++ b/app/models/order.rb
@@ -50,7 +50,7 @@ class Order < ActiveRecord::Base
       # but which have already been ordered in this stock order
       StockArticle.available.includes(:article_category).
         order('article_categories.name', 'articles.name').reject{ |a|
-        a.quantity_available <= 0 and not a.ordered_in_order?(self)
+        a.quantity_available <= 0 && !a.ordered_in_order?(self)
       }.group_by { |a| a.article_category.name }
     else
       supplier.articles.available.group_by { |a| a.article_category.name }
@@ -260,8 +260,8 @@ class Order < ActiveRecord::Base
   def keep_ordered_articles
     chosen_order_articles = order_articles.where(article_id: article_ids)
     to_be_removed = order_articles - chosen_order_articles
-    to_be_removed_but_ordered = to_be_removed.select { |a| a.quantity > 0 or a.tolerance > 0 }
-    unless to_be_removed_but_ordered.empty? or ignore_warnings
+    to_be_removed_but_ordered = to_be_removed.select { |a| a.quantity > 0 || a.tolerance > 0 }
+    unless to_be_removed_but_ordered.empty? || ignore_warnings
       errors.add(:articles, I18n.t(stockit? ? 'orders.model.warning_ordered_stock' : 'orders.model.warning_ordered'))
       @erroneous_article_ids = to_be_removed_but_ordered.map { |a| a.article_id }
     end
diff --git a/app/models/order_article.rb b/app/models/order_article.rb
index 5666a549..ef894166 100644
--- a/app/models/order_article.rb
+++ b/app/models/order_article.rb
@@ -122,13 +122,13 @@ class OrderArticle < ActiveRecord::Base
     qty_left -= qty_for_members
 
     # if there's anything left, move to stock if wanted
-    if qty_left > 0 and surplus.index(:stock)
+    if qty_left > 0 && surplus.index(:stock)
       counts[surplus.index(:stock)] = qty_left
       # 1) find existing stock article with same name, unit, price
       # 2) if not found, create new stock article
       #      avoiding duplicate stock article names
     end
-    if qty_left > 0 and surplus.index(nil)
+    if qty_left > 0 && surplus.index(nil)
       counts[surplus.index(nil)] = qty_left
     end
 
@@ -181,7 +181,7 @@ class OrderArticle < ActiveRecord::Base
   end
 
   def update_global_price=(value)
-    @update_global_price = (value == true or value == '1') ?  true : false
+    @update_global_price = (value == true || value == '1') ?  true : false
   end
 
   # @return [Number] Units missing for the last +unit_quantity+ of the article.
@@ -207,7 +207,7 @@ class OrderArticle < ActiveRecord::Base
 
   # Associate with current article price if created in a finished order
   def init_from_balancing
-    if order.present? and order.finished?
+    if order.present? && order.finished?
       self.article_price = article.article_prices.first
     end
   end
diff --git a/app/models/ordergroup.rb b/app/models/ordergroup.rb
index 0f5faf12..153ff379 100644
--- a/app/models/ordergroup.rb
+++ b/app/models/ordergroup.rb
@@ -85,11 +85,11 @@ class Ordergroup < Group
   # The restriction can be deactivated for each ordergroup.
   # Only ordergroups, which have participated in more than 5 orders in total and more than 2 orders in apple time period
   def not_enough_apples?
-    FoodsoftConfig[:use_apple_points] and
-        FoodsoftConfig[:stop_ordering_under].present? and
-        !ignore_apple_restriction and
-        apples < FoodsoftConfig[:stop_ordering_under] and
-        group_orders.count > 5 and
+    FoodsoftConfig[:use_apple_points] &&
+        FoodsoftConfig[:stop_ordering_under].present? &&
+        !ignore_apple_restriction &&
+        apples < FoodsoftConfig[:stop_ordering_under] &&
+        group_orders.count > 5 &&
         group_orders.joins(:order).merge(Order.finished).where('orders.ends >= ?', APPLE_MONTH_AGO.month.ago).count > 2
   end
 
diff --git a/app/models/supplier.rb b/app/models/supplier.rb
index 9624eafb..6332aad7 100644
--- a/app/models/supplier.rb
+++ b/app/models/supplier.rb
@@ -39,7 +39,7 @@ class Supplier < ActiveRecord::Base
           
           # try to convert different units
           new_price, new_unit_quantity = article.convert_units
-          if new_price and new_unit_quantity
+          if new_price && new_unit_quantity
             article.price = new_price
             article.unit_quantity = new_unit_quantity
           else
@@ -98,7 +98,7 @@ class Supplier < ActiveRecord::Base
 
   # make sure the shared_sync_method is allowed for the shared supplier
   def valid_shared_sync_method
-    if shared_supplier and !shared_supplier.shared_sync_methods.include?(shared_sync_method)
+    if shared_supplier && !shared_supplier.shared_sync_methods.include?(shared_sync_method)
       errors.add :name, :included
     end
   end
diff --git a/app/models/user.rb b/app/models/user.rb
index 3ab99d85..cfd69806 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -160,7 +160,7 @@ class User < ActiveRecord::Base
   end
 
   def self.authenticate(login, password)
-    user = (find_by_nick(login) or find_by_email(login))
+    user = find_by_nick(login) || find_by_email(login)
     if user && user.has_password(password)
       user
     else
diff --git a/lib/capistrano/tasks/deploy_initial.cap b/lib/capistrano/tasks/deploy_initial.cap
index b33cac79..63c64875 100644
--- a/lib/capistrano/tasks/deploy_initial.cap
+++ b/lib/capistrano/tasks/deploy_initial.cap
@@ -23,7 +23,7 @@ namespace :deploy do
       task :config => ['deploy:set_rails_env'] do
         require 'securerandom'
         on roles(:app), in: :groups do
-          db_name = (fetch(:db_user) or fetch(:application))
+          db_name = fetch(:db_user) || fetch(:application)
           db_passwd = SecureRandom.urlsafe_base64(24).to_s
           db_yaml = {
             fetch(:rails_env).to_s => {
diff --git a/lib/capistrano/tasks/plugins.cap b/lib/capistrano/tasks/plugins.cap
index d0a2c0e0..7d6c95da 100644
--- a/lib/capistrano/tasks/plugins.cap
+++ b/lib/capistrano/tasks/plugins.cap
@@ -28,7 +28,7 @@ namespace :enable_plugins do
       text = capture :cat, shared_path.join('config/plugins.yml'), '||true'
       if text
         plugins = YAML.load(text)
-        enable_foodsoft_plugins(plugins['enabled']) if plugins and not plugins['enabled'].nil?
+        enable_foodsoft_plugins(plugins['enabled']) if plugins && !plugins['enabled'].nil?
       end
     end
   end
diff --git a/lib/capistrano/tasks/resque.cap b/lib/capistrano/tasks/resque.cap
index 02f9898f..ff7f32a3 100644
--- a/lib/capistrano/tasks/resque.cap
+++ b/lib/capistrano/tasks/resque.cap
@@ -11,7 +11,7 @@ namespace :resque do
       on roles(:resque), in: :groups do
 
         SSHKit.config.command_map[:rake_as_run_user] =
-          unless fetch(:run_user).nil? or fetch(:run_user) == fetch(:user)
+          unless fetch(:run_user).nil? || fetch(:run_user) == fetch(:user)
             "sudo -u '#{fetch(:run_user)}' "
           else
             ''
diff --git a/lib/date_time_attribute_validate.rb b/lib/date_time_attribute_validate.rb
index 1b73fc3b..0e697ce7 100644
--- a/lib/date_time_attribute_validate.rb
+++ b/lib/date_time_attribute_validate.rb
@@ -19,7 +19,7 @@ module DateTimeAttributeValidate
           if self.instance_variable_get("@#{attribute}_is_set")
             date = self.instance_variable_get("@#{attribute}_date_value")
             time = self.instance_variable_get("@#{attribute}_time_value")
-            if date.blank? and time.blank?
+            if date.blank? && time.blank?
               self.send("#{attribute}=", nil)
             end
           end
@@ -50,11 +50,11 @@ module DateTimeAttributeValidate
         # validate date and time
         define_method("#{attribute}_datetime_value_valid") do
           date = self.instance_variable_get("@#{attribute}_date_value")
-          unless date.blank? or (Date.parse(date) rescue nil)
+          unless date.blank? || (Date.parse(date) rescue nil)
             errors.add(attribute, "is not a valid date") # @todo I18n
           end
           time = self.instance_variable_get("@#{attribute}_time_value")
-          unless time.blank? or (Time.parse(time) rescue nil)
+          unless time.blank? || (Time.parse(time) rescue nil)
             errors.add(attribute, "is not a valid time") # @todo I18n
           end
         end
diff --git a/lib/foodsoft_config.rb b/lib/foodsoft_config.rb
index d03cd283..f6662bf9 100644
--- a/lib/foodsoft_config.rb
+++ b/lib/foodsoft_config.rb
@@ -94,7 +94,7 @@ class FoodsoftConfig
     # @param key [String, Symbol]
     # @return [Object] Value of the key.
     def [](key)
-      if RailsSettings::CachedSettings.table_exists? and allowed_key?(key)
+      if RailsSettings::CachedSettings.table_exists? && allowed_key?(key)
         value = RailsSettings::CachedSettings["foodcoop.#{self.scope}.#{key}"]
         value = config[key] if value.nil?
         value
@@ -113,7 +113,7 @@ class FoodsoftConfig
       return false unless allowed_key?(key)
       value = normalize_value value
       # then update database
-      if config[key] == value or (config[key].nil? and value == false)
+      if config[key] == value || (config[key].nil? && value == false)
         # delete (ok if it was already deleted)
         begin
           RailsSettings::CachedSettings.destroy "foodcoop.#{self.scope}.#{key}"
diff --git a/lib/foodsoft_date_util.rb b/lib/foodsoft_date_util.rb
index 2fa5febb..9b7ba6ac 100644
--- a/lib/foodsoft_date_util.rb
+++ b/lib/foodsoft_date_util.rb
@@ -7,7 +7,7 @@ module FoodsoftDateUtil
       # @todo handle ical parse errors
       occ = (schedule.next_occurrence(from).to_time rescue nil)
     end
-    if occ and options[:time]
+    if occ && options[:time]
       occ = occ.beginning_of_day.advance(seconds: Time.parse(options[:time]).seconds_since_midnight)
     end
     occ
diff --git a/lib/tasks/foodsoft.rake b/lib/tasks/foodsoft.rake
index 00e741df..bfe94319 100644
--- a/lib/tasks/foodsoft.rake
+++ b/lib/tasks/foodsoft.rake
@@ -42,7 +42,7 @@ namespace :foodsoft do
       if tg.has_next_task?
         create_until = Date.today + FoodsoftConfig[:tasks_upfront_days].to_i + 1
         rake_say "creating until #{create_until}"
-        while tg.next_task_date.nil? or tg.next_task_date < create_until
+        while tg.next_task_date.nil? || tg.next_task_date < create_until
           tg.create_next_task
         end
       end
diff --git a/lib/tasks/foodsoft_setup.rake b/lib/tasks/foodsoft_setup.rake
index f6c0bd65..74b7d6b0 100644
--- a/lib/tasks/foodsoft_setup.rake
+++ b/lib/tasks/foodsoft_setup.rake
@@ -126,7 +126,7 @@ end
 def ask(question, answers = false)
   puts question
   input = STDIN.gets.chomp
-  if input.blank? or (answers and !answers.include?(input))
+  if input.blank? || (answers && !answers.include?(input))
     puts red "Your Input is not valid. Try again!"
     input = ask(question, answers)
   end
diff --git a/lib/token_verifier.rb b/lib/token_verifier.rb
index bd936a4e..0e973a42 100644
--- a/lib/token_verifier.rb
+++ b/lib/token_verifier.rb
@@ -15,7 +15,7 @@ class TokenVerifier < ActiveSupport::MessageVerifier
 
   def verify(message)
     r = super(message)
-    raise InvalidMessage unless r.is_a?(Array) and r.length >= 2 and r.length <= 3
+    raise InvalidMessage unless r.is_a?(Array) && r.length >= 2 && r.length <= 3
     raise InvalidScope unless r[0] == FoodsoftConfig.scope
     raise InvalidPrefix unless r[1] == @_prefix
     # return original message
@@ -34,7 +34,7 @@ class TokenVerifier < ActiveSupport::MessageVerifier
 
   def self.secret
     # secret_key_base for Rails 4, but Rails 3 initializer may still be used
-    Foodsoft::Application.config.secret_key_base or Foodsoft::Application.config.secret_token
+    Foodsoft::Application.config.secret_key_base || Foodsoft::Application.config.secret_token
   end
 
 end
diff --git a/plugins/messages/app/controllers/messages_controller.rb b/plugins/messages/app/controllers/messages_controller.rb
index 2348616d..78c2db08 100644
--- a/plugins/messages/app/controllers/messages_controller.rb
+++ b/plugins/messages/app/controllers/messages_controller.rb
@@ -10,7 +10,7 @@ class MessagesController < ApplicationController
   # Creates a new message object.
   def new
     @message = Message.new(params[:message])
-    if @message.reply_to and not @message.reply_to.is_readable_for?(current_user)
+    if @message.reply_to && !@message.reply_to.is_readable_for?(current_user)
       redirect_to new_message_url, alert: 'Nachricht ist privat!'
     end
   end
diff --git a/plugins/messages/lib/foodsoft_messages/user_link.rb b/plugins/messages/lib/foodsoft_messages/user_link.rb
index 2278ebf2..aa34bf46 100644
--- a/plugins/messages/lib/foodsoft_messages/user_link.rb
+++ b/plugins/messages/lib/foodsoft_messages/user_link.rb
@@ -6,7 +6,7 @@ module FoodsoftMessages
 
         # modify user presentation link to writing a message for the user
         def show_user_link(user=@current_user)
-          if user.nil? or not FoodsoftMessages.enabled?
+          if user.nil? || !FoodsoftMessages.enabled?
             show_user user
           else
             link_to show_user(user), new_message_path('message[mail_to]' => user.id),
diff --git a/plugins/uservoice/lib/foodsoft_uservoice.rb b/plugins/uservoice/lib/foodsoft_uservoice.rb
index 0bf5a494..d8942d89 100644
--- a/plugins/uservoice/lib/foodsoft_uservoice.rb
+++ b/plugins/uservoice/lib/foodsoft_uservoice.rb
@@ -4,7 +4,7 @@ require "foodsoft_uservoice/engine"
 module FoodsoftUservoice
   # enabled when configured, but can still be disabled by use_uservoice option
   def self.enabled?
-    FoodsoftConfig[:use_uservoice] != false and FoodsoftConfig[:uservoice]
+    FoodsoftConfig[:use_uservoice] != false && FoodsoftConfig[:uservoice]
   end
 
   module LoadUservoice
diff --git a/plugins/wiki/app/controllers/pages_controller.rb b/plugins/wiki/app/controllers/pages_controller.rb
index d8114e96..ab6b5426 100644
--- a/plugins/wiki/app/controllers/pages_controller.rb
+++ b/plugins/wiki/app/controllers/pages_controller.rb
@@ -84,7 +84,7 @@ class PagesController < ApplicationController
     else
       if @page.save
         @page.parent_id = parent_id if (!params[:parent_id].blank? \
-            and params[:parent_id] != @page_id)
+            && params[:parent_id] != @page_id)
         flash[:notice] = I18n.t('pages.update.notice')
         redirect_to wiki_page_path(@page.permalink)
       else
diff --git a/plugins/wiki/app/helpers/pages_helper.rb b/plugins/wiki/app/helpers/pages_helper.rb
index 6f93837e..e8afccc1 100644
--- a/plugins/wiki/app/helpers/pages_helper.rb
+++ b/plugins/wiki/app/helpers/pages_helper.rb
@@ -62,7 +62,7 @@ module PagesHelper
 
   def parent_pages_to_select(current_page)
     unless current_page.homepage? # Homepage is the page trees root!
-      Page.non_redirected.reject { |p| p == current_page or p.ancestors.include?(current_page) }
+      Page.non_redirected.reject { |p| p == current_page || p.ancestors.include?(current_page) }
     else
       Array.new
     end
diff --git a/plugins/wiki/app/views/pages/_body.html.haml b/plugins/wiki/app/views/pages/_body.html.haml
index cc06bc6b..bca94ff2 100644
--- a/plugins/wiki/app/views/pages/_body.html.haml
+++ b/plugins/wiki/app/views/pages/_body.html.haml
@@ -1,7 +1,7 @@
 - content = wikified_body @page.body, @page.title
 - toc = generate_toc @page.body
 
-- unless toc.blank? or params[:preview]
+- unless toc.blank? || params[:preview]
   - content_for :sidebar do
     #wikitoc.well.well-small
       %h3= t '.title_toc'