Example digits „1301“ could be following:

1. PIN (Computer, Phone, Game, TV, ATM, Locker, KeyLock ...)
2. Year (Chinese, ...)
3. Hours and Minutes
4. Day and Month
5. Phone number (Services, ...)
6. Number of letter (0 - [Space], A - 1, B – 2, C – 3, ...)
7. Lipstik (Leet Speak)
8. Number (Hex, Dec, Oct ...)
9. Part of registration plates
10. Reversed or scrambled
11. Combination any of these above
12. Random digits
13. Something else

FireFox Keyboard Shortcuts

Firefox:
CTRL + SHIFT + P (Private Browsing)
CTRL + T (New Tab)
CTRL + ALT (Switch between tabs)
CTRL + W (Close Tab)
CTRL + H (Show/Hide History)
CTRL + J (Shows downloads)
CTRL + F or F3 - Find/Find next
F5 (Refresh webpage)
F11 - Full Screen Mode/Exit Full Screen Mode
ALT + Left Arrow - Page Back (12.09.2020)
ALT + Right Arrow - Page Forward (12.09.2020)
ALT, f, x (EXIT)

Word Keyboard Shortcuts

Word:

BACKSPACE (deletes character on left from blinking cursor)
DELETE (deletes character on right from blinking cursor)

CTRL + Z (Undo)
CTRL + S (Save)


CTRL + A (Selects everything)
CTRL + C (Copy)
CTRL + V (Paste)
CTRL + X (Cut)

CTRL + F (Find...)

CTRL + B (Bold)
CTRL + I (Italic)
CTRL + U (Underline)

ENTER (New Paragraph)
SHIFT + ENTER (New line)
CTRL + ENTER (Page Break New Page)

HOME (Beginning of line)
END (End of line)

SHIFT + F3 (Switch case)

CTRL + HOME (Anchor goes to Start of document)
CTRL + END (Anchor goes to End of document)

CTRL + Right Arrow (word by word)
CTRL + Left Arrow (word by word)

SHIFT + Up Arrow
SHIFT + Down Arrow

SHIFT + END (Selects all from left to right relative to blinking cursor)
Example: H|ello -->  Hello|

SHIFT + HOME (Selects all from right to left relative to blinking cursor)
Example: Hello what|'s app? --> |Hello what's app?

CTRL + SHIFT + END (Depending on where blinking cursor is selects all from left of to right to end of document)
CTRL + SHIFT + HOME (Depending on where blinking cursor is selects all from right to left till start of document)

PAGE UP (Goes from current page to previous page)
PAGE DOWN (Goes from current page to next page)

Practice, practice, practice...

LinuxLive USB Creator

Simply named LiLi.
https://www.linuxliveusb.com/

Windows 7 KeyBoard Shortcuts

Windows 7:

F1 (Help)
F2 (Rename)
CTRL + C (Copy)
CTRL + V (Paste)
CTRL + X (Cut)

CTRL + Z (Undo last operation)
CTRL + A (Select all)

ALT + TAB (Change between programs)
CTRL + ALT + DELETE (Calls options)
CTRL + SHIFT + ESC (Calls Task Manager)
CTRL + SHIFT + N (Creates New Folder)
LEFT ALT + LEFT SHIFT + NUM LOCK (use keyboard as mouse)
WIN + R (Run Task)
WIN + F (Search)
WIN + D (Desktop)
WIN + E (Computer)
WIN + L (Lock Screen)

TAB (next object)
SHIFT + TAB (previous object)

WIN, RIGHT ARROW, ENTER (Shutdown)
ALT + F4 (Close Window)
PRINT SCREEN (Takes screenshot)
ALT + PRT SCR (Takes screenshot of focused window)
ALT GRAPH + X (Editing Screenshot)
WIN+R, type "cmd", ENTER (Run command prompt)

CAPS LOCK ON (UPPER CASE)
CAPS LOCK OFF (lower case)

INSERT ON (Over type)
INSERT OFF (No over type)

DELETE - send folder (with subfolders and files if there is any) or file(s) to Recycle Bin.
SHIFT + DELETE - Permanently delete file

For those who want to know more:
Windows 7: Open Explorer; Click on top right corner blue question mark button and select View Help (blue book)
Search for "keyboard" in your system's language and there it should be in those links full Key Shortcut list for Windows 7. Depending on what you need.