Multiple Lessons: Update notes

databases/databases/databases_and_sql.md

@@ -72,9 +72,11 @@ A close cousin of `SELECT`, for if you only want unique values of a column, is `
 
 If you want to get all the posts created by a given user, you need to tell SQL which columns it should use to zip the tables together with the `ON` clause. Perform the "zipping" with the `JOIN` command.  But wait, if you mash two tables together where the data doesn't perfectly match up (e.g. there are multiple posts for one user), which rows do you actually keep?  There are four different possibilities:
 
-_(__note:__ the "left" table is the original table (the one that the `FROM` clause was `ON`), e.g. "users" in examples below.)_
+<div class="lesson-note lesson-note--tip" markdown="1">
 
-*See ["A Visual Explanation of SQL Joins"](http://blog.codinghorror.com/a-visual-explanation-of-sql-joins) by Jeff Atwood for good visuals.*
+The "left" table is the original table (the one that the `FROM` clause was `ON`), e.g. "users" in examples below.
+
+</div>
 
 1. `INNER JOIN`, aka `JOIN` -- Your best friend and 95% of what you'll use.  <span id='inner-join'>Keeps only the rows from both tables where they match up</span>.  If you asked for all the posts for all users (`SELECT * FROM users JOIN posts ON users.id = posts.user_id`), it would return only the users who have actually written posts and only posts which have specified their author in the `user_id` column.  If an author has written multiple posts, there will be multiple rows returned (but the columns containing the user data will just be repeated).
 2. `LEFT OUTER JOIN` -- keep all the rows from the left table and add on any rows from the right table which match up to the left table's.  Set any empty cells this produces to `NULL`.  E.g. return all the users whether they have written posts or not.  If they do have posts, list those posts as above.  If not, set the columns we asked for from the "posts" table to `NULL`.
@@ -83,6 +85,8 @@ _(__note:__ the "left" table is the original table (the one that the `FROM` clau
 
 Joins naturally let you specify conditions too, like if you only want the posts from a specific user: `SELECT * FROM users JOIN posts ON users.id = posts.user_id WHERE users.id = 42`.
 
+*See ["A Visual Explanation of SQL Joins"](http://blog.codinghorror.com/a-visual-explanation-of-sql-joins) by Jeff Atwood for good visuals.*
+
 Read through [W3 Schools' Joins lesson](http://www.w3schools.com/sql/sql_join.asp) for a better explanation.
 
 #### Using functions to aggregate your data

foundations/installations/installations.md

@@ -84,7 +84,11 @@ In the **Hardware** section of the installation you want to set your **Base Memo
 
 For example, if you have 8 GB (8192 MB respectively) of RAM, you could allocate up to 4096 MB (1024 MB to 1 GB) to your VM’s operating system. If you do not know how much RAM is available to you, [please run this Google query](https://www.google.com/search?q=how+to+find+out+how+much+ram+you+have) to learn how to find this out. If the VM runs a bit slow, try allocating more memory!
 
-_(__note:__ Difficulty converting your **G**iga**B**ytes into **M**ega**B**ytes? 1 GB of RAM is equal to 1024 MB. Therefore, you can say that **8 GB = 8 x 1024 = 8192 MB.**)_
+<div class="lesson-note lesson-note--tip" markdown="1">
+
+Difficulty converting your Gigabytes (GB) into Megabytes (MB)? 1 GB of RAM is equal to 1024 MB. Therefore, you can say that <b>8 GB = 8 x 1024 = 8192 MB.</b>
+
+</div>
 
 As for **Processors** you want this to be at 2 and no more. Leave **Enable EFI (special OSes only)** as it is - that is **unchecked** - and click **Next** to continue.
 
@@ -300,7 +304,11 @@ wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
 
    -   Enter your password, if needed
 
-   _(__note__: You might see a notice starting with `N: Download is performed unsandboxed (...)`. You don't need to worry about it. [Read this reddit post for more information.](https://www.reddit.com/r/linux4noobs/comments/ux6cwx/comment/i9x2twx/))_
+<div class="lesson-note lesson-note--tip" markdown="1">
+
+You might see a notice starting with `N: Download is performed unsandboxed (...)`. You don't need to worry about it. [Read this reddit post for more information.](https://www.reddit.com/r/linux4noobs/comments/ux6cwx/comment/i9x2twx/))_
+
+</div>
 
 #### Step 3: Delete the installer file
 
@@ -319,7 +327,11 @@ You can start chrome in two ways,
 google-chrome
 ~~~
 
-_(__note__: Chrome is going to use this terminal to output various messages and won't let you run other commands. Don't worry about those messages. If you want to use the same terminal that you run Chrome in for other commands, use `google-chrome &` instead.)_
+<div class="lesson-note lesson-note--tip" markdown="1">
+
+Chrome is going to use this terminal to output various messages and won't let you run other commands. Don't worry about those messages. If you want to use the same terminal that you run Chrome in for other commands, use `google-chrome &` instead.)_
+
+</div>
 
 </details>
 

foundations/installations/text_editors.md

@@ -42,7 +42,11 @@ sudo apt install ./code-latest.deb
 
    - If prompted, enter your password
 
-   _(__note__: You might see a notice starting with `N: Download is performed unsandboxed (...)`. You don't need to worry about it. [Read this reddit post for more information.](https://www.reddit.com/r/linux4noobs/comments/ux6cwx/comment/i9x2twx/))_
+<div class="lesson-note lesson-note--tip" markdown="1">
+
+You might see a notice starting with `N: Download is performed unsandboxed (...)`. You don't need to worry about it. [Read this reddit post for more information.](https://www.reddit.com/r/linux4noobs/comments/ux6cwx/comment/i9x2twx/))_
+
+</div>
 
 #### Step 3: Delete the installer file