sich maskieren
to disguise oneself
To cover one's face with a mask or another disguise in order not to be recognized.
Die Bankräuber hatten sich mit Skimasken maskiert.
The bank robbers had disguised themselves with ski masks.

to mask
Loading your saved state.
to disguise oneself
To cover one's face with a mask or another disguise in order not to be recognized.
Die Bankräuber hatten sich mit Skimasken maskiert.
The bank robbers had disguised themselves with ski masks.

The verb 'maskieren' (to mask) is derived directly from the noun 'die Maske' (mask). In all meanings, it is about covering something with a kind of 'Maske' (mask), whether literally or figuratively.
An Karneval tragen viele Menschen eine Maske.
At Carnival, many people wear a mask.
When a person covers their own face, the verb is used reflexively: 'sich maskieren' (to disguise oneself). In all other meanings, it is transitive and needs an accusative object: 'etwas maskieren' (to mask something).
Der Schauspieler maskiert sich vor dem Auftritt.
The actor disguises himself before the performance.
In the figurative sense, 'maskieren' (to mask) is often used with abstract nouns. Typical combinations are 'seine Gefühle maskieren' (to mask one's feelings), 'seine Unsicherheit maskieren' (to mask one's insecurity), or 'die wahren Absichten maskieren' (to mask the true intentions).
Sie konnte ihre Enttäuschung nur schwer maskieren.
She could only barely mask her disappointment.
In a craft or DIY context, 'maskieren' (to mask) means to cover a surface with tape ('Kreppband', masking tape) or film in order to protect it while painting or varnishing.
Bevor du die Decke streichst, musst du die Ränder der Wände sauber maskieren.
Before you paint the ceiling, you have to neatly mask the edges of the walls.
In IT, 'maskieren' (to mask) means to make sensitive data such as passwords, credit card numbers, or IP addresses unreadable in order to protect privacy and security.
Wenn Sie Ihr Passwort eingeben, werden die Zeichen automatisch maskiert.
When you enter your password, the characters are automatically masked.
to hide / conceal
'verbergen' and 'maskieren' can both mean that you do not show something openly. 'verbergen' is more general: you keep a feeling, intention, or piece of information secret. 'maskieren' is more appropriate when something is meant to appear different on the outside from what it really is. So you are not only hiding something, but giving it a kind of false surface. With feelings, 'verbergen' sounds more natural when someone does not want to show anything. 'maskieren' is more precise when someone disguises a feeling or intention through different behavior.

Er maskiert seine Unsicherheit oft mit lauten Witzen.
He often masks his insecurity with loud jokes.
Sie konnte ihre Enttäuschung im Gespräch kaum verbergen.
She could barely conceal her disappointment during the conversation.