In Netcrawl there are three broad categories of skills: Security, Investigative, and Code Execution.
Every Avatar in Netcrawl RPG can attempt to perform these skills in the metaverse.
The exact mechanics of being trained differ based on the type of skill.

Security Skills

Security skills require difficulty checks vs a target number or DC. If the skill is trained, the character rolls 1d20 for the check. Otherwise, they roll 1d10.

Breach Security: This skill governs breaking into secured systems without proper permissions. Plainly put, the character is attempting to break into secured systems.

Falsify Identity: The art of spoofing or otherwise appearing to be something one is not. Successful use allows the character to blend in with the surrounding system and produce proper identifiers. Being able to provide many false identities that pass cursory examination is key to a successful system raid.

Null Trace: Artfully removing one's trace or logged records is a paramount concern of raiders. This skill allows the character to delete access records, remove/prevent trackers, or evade active pursuit.

Investigative

Investigative skills are special in that they automatically reveal information or clues. That's right - as long as the PC is trained and can afford to spend a turn information is revealed. Stressful situations, limited time, or extremely difficult clues may call for a roll (if the skill is trained, the character rolls 1d20 for the check. Otherwise, they roll 1d10).

Data Analysis: The ability to quickly scan data for patterns or information. This skill allows an avatar to discern the difference between real and planted data or find an exact piece or collection of information. Data analysis reveals the basic meaning or subject of a piece of content, but also goes beyond simple interpretation into determining veracity & provenance of data and locating specific data from tera-bytes of other information.

Intuit Architecture: A computer system is its own environment and avatars have gained enough exposure to those ecosystems to allow them a hunch about what the next system element (aka - hex) might contain or in which direction their quarry (likely some information somewhere) lies. Successful use of this skill gives a character a clue or outright knowledge about surrounding nodes or levels including things like backdoors or other hidden facts.

Code Execution

Any character can attempt to execute code. The code must be accessible in the form of a recorded program or script (kind of like reading a scroll in a fantasy TTRPG). Code can exist inside a device, creature, or fixture (e.g., a control panel or whirling vortex of machine code, etc.). 

Trained characters receive roll a 1d12 to activate the code; untrained characters use 1d10. A Cybernaut is already trained (rolling 1d12) in this skill. So it will not be in our campaign's poll.

Each avatar may declare one skill that they are considered trained in (except Grifters who are skilled in all the base Netcrawl skills).