Incierto vs. inseguro
The Spanish words 'incierto' and 'inseguro' are often used interchangeably, but they have subtle differences in meaning and usage.
Incierto
'Incierto' primarily means uncertain or doubtful, referring to situations or outcomes that are not definite or clear.
El futuro de la empresa es incierto debido a la crisis económica.
(The future of the company is uncertain due to the economic crisis.)
El pronóstico del tiempo para mañana es incierto.
(The weather forecast for tomorrow is uncertain.)
Inseguro
'Inseguro' can mean insecure or unsafe, often relating to personal feelings or physical safety, but it can also mean uncertain in some contexts.
Me siento inseguro hablando en público.
(I feel insecure speaking in public.)
Este barrio es inseguro por la noche.
(This neighborhood is unsafe at night.)
Estoy inseguro sobre qué decisión tomar.
(I'm uncertain about which decision to make.)
Summary
While 'incierto' primarily refers to uncertainty in situations or outcomes, 'inseguro' can mean both insecure/unsafe and uncertain, depending on the context. 'Incierto' is more often used for external circumstances, while 'inseguro' can describe both external situations and personal feelings.